This document provides a review of recent advances in perovskite solar cell technology. Key points include:
- Perovskite solar cells have significantly higher efficiencies than organic solar cells and dye-sensitized solar cells, with efficiencies increasing from 9.6% in 2012 to over 20% in 2015 for lead-based perovskites.
- Perovskites have the formula ABX3 and a specific crystal structure that enables their photovoltaic properties.
- While perovskite solar cells show great potential, issues of stability, toxicity from lead, and degradation with humidity and UV light need further addressing for commercialization.
The document discusses the origin of radiation-induced degradation in polymer solar cells. It finds that charge accumulation at the interface is the primary reason for degradation, affected by the donor-acceptor mixing ratio in the bulk heterojunction. In situ measurements of polymer solar cell performance and recombination lifetimes under X-ray radiation show that devices with high acceptor concentrations experience a significant decrease in open-circuit voltage and fill factor due to radiation, while devices with low acceptor concentrations are more resistant to these changes. The findings provide a quantitative understanding and physical model of the degradation mechanism.
Boosting Photocatalytic Activity Using Carbon Nitride Based 2D/2D van der Waa...Pawan Kumar
The surging demand for energy and staggering pollutants in the environment have geared the scientific community to explore sustainable pathways that are economically feasible and environmentally compelling. In this context, harnessing solar energy using semiconductor materials to generate charge pairs to drive photoredox reactions has been envisioned as a futuristic approach. Numerous inorganic crystals with promising nanoregime properties investigated in the past decade have yet to demonstrate practical application due to limited photon absorption and sluggish charge separation kinetics. Two-dimensional semiconductors with tunable optical and electronic properties and quasi-resistance-free lateral charge transfer mechanisms have shown great promise in photocatalysis. Polymeric graphitic carbon nitride (g-C3N4) is among the most promising candidates due to fine-tuned band edges and the feasibility of optimizing the optical properties via materials genomics. Constructing a two-dimensional (2D)/2D van der Waals (vdW) heterojunction by allies of 2D carbon nitride sheets and other 2D semiconductors has demonstrated enhanced charge separation with improved visible photon absorption, and the performance is not restricted by the lattice matching of constituting materials. With the advent of new 2D semiconductors over the recent past, the 2D/2D heterojunction assemblies are gaining momentum to design high performance photocatalysts for numerous applications. This review aims to highlight recent advancements and key understanding in carbon nitride based 2D/2D heterojunctions and their applications in photocatalysis, including small molecules activation, conversion, and degradations. We conclude with a forward-looking perspective discussing the key challenges and opportunity areas for future research.
IRJET - Advances in Perovskite Solar CellsIRJET Journal
This document summarizes recent advances in perovskite solar cells. It discusses how perovskite solar cell efficiency has rapidly increased from 3.8% in 2009 to over 24.2% today, catching up to silicon solar cells. The stability of perovskite structures depends on factors like ionicity and tolerance factor. While perovskite solar cells still face stability issues with water and temperature, encapsulation and tandem cell designs with silicon are helping to address this. Research is ongoing to improve materials, device architectures and manufacturing techniques to further increase efficiency and commercial viability of these promising thin film solar cells.
Photo-assisted oxidation of thiols to disulfides using cobalt ‘‘Nanorust’’ un...Pawan Kumar
Heterogeneous ‘‘Nanorust’’ containing cobalt oxide has been developed for the visible light assisted
oxidation of thiols to disulfides using molecular oxygen as an oxidant under alkaline free conditions and
therefore more environmentally friendly. Pyrolysis of heterogenized tetrasulfonated cobalt(II) phthalocyanine
(CoPcS) supported on mesoporous ceria (CeO2) transforms it into a novel heterogeneous ‘‘Nanorust’’
containing CoOx-C,N@CeO2 which exhibited higher catalytic activity than the homogeneous CoPcS as well
as the ceria immobilized CoPcS catalyst. Importantly, these catalysts could easily be recovered and recycled
for several runs, which makes the process greener and cost-effective.
1) The document describes the development of a new oxynitride-based phosphor called Y10Al2Si3O18N4:Re3+ (YAlSiON:Re3+) that can efficiently convert near-UV light from LEDs into blue, green, and orange colors.
2) By controlling the composition, the phosphor can produce tricolor emission without reabsorption of green and orange light in the blue region.
3) Energy transfer mechanisms allow production of blue light from Ce3+, green light from Ce3+-Tb3+ transfer, and orange light from Ce3+ → Tb3+ → Eu3+ transfer, enabling full-color emission from a
Heterostructured nanocomposite tin phthalocyanine@mesoporous ceria (SnPc@CeO2...Pawan Kumar
Heterostructured tin phthalocyanine supported to mesoporous ceria was synthesized and used a
photocatalyst for CO2 reduction under visible light. The photoreduction CO2 activities of the
heterostructures were investigated in the presence of triethylamine as sacrificial agent. The developed
photocatalyst exhibited high catalytic activity for photoreduction of CO2 and after 24 hours of visible
light irradiation 2342 mmol g1 cat of methanol (fMeOH ¼ 0.0223 or 2.23%) and 840 mmol g1 cat of CO
(fCO ¼ 0.0026 or 0.26%) were obtained as the major reaction products. The methanol formation rate
(RMeOH) and CO formation rate (RCO) was found to be 97.5 mmol h1 g1 cat and 35.0 mmol h1 g1 cat
respectively. While under the identical experimental conditions mesoporous ceria (meso-CeO2) gave
only 316 mmol g1 cat of methanol (fMeOH ¼ 0.003 or 0.30%) and 126 mmol g1 cat CO (fCO ¼ 0.0004
or 0.04%) with product formation rate RMeOH ¼ 13.2 mmol h1 g1 cat and RCO ¼ 5.3 mmol h1 g1 cat.
Furthermore, the recovered catalyst showed consistent catalytic activity for at least five runs without any
significant loss in product yields
Polymeric carbon nitride-based photocatalysts for photoreforming of biomass d...Pawan Kumar
Photoreforming of biomass to value-added chemicals and fuels is a chemical approach to extract photosynthetically-trapped energy in complex biomolecules which otherwise disintegrate naturally in the environment. Designing precise photocatalytic materials that can selectively break the sturdy, nature-designed biomass with multiplex chemical composition/bonding and inaccessible sites is central to deploying this technology. Polymeric carbon nitride (CN) comprised of a 2D network of condensed heptazine/triazine (C6N7/C3N3) core has shown great promise for photoreforming of biomass derivatives due to intriguing physicochemical and optical properties. This review comprehensively summarizes the state-of-the-art applications of CN-based photocatalysts for the conversion of lignocellulosic biomass derivatives. Various chemical and structural modifications in CN structure such as doping, surface functionalization, hybridization entailing to higher selectivity and conversion have been discussed aiming at providing valuable guidance for future CN-based materials design.
This document discusses X-ray diffraction (XRD) spectroscopy and provides examples of applying XRD principles to characterize different materials. It describes the basic principles of how XRD works using Bragg's law and Miller indices to identify crystal planes. Examples are given for characterizing silver nanoparticles, graphite, graphene oxide, and zinc oxide nanoparticles using XRD, including estimating particle sizes from XRD peak widths and identifying functional groups from infrared spectroscopy. References are also provided for further reading.
The document discusses the origin of radiation-induced degradation in polymer solar cells. It finds that charge accumulation at the interface is the primary reason for degradation, affected by the donor-acceptor mixing ratio in the bulk heterojunction. In situ measurements of polymer solar cell performance and recombination lifetimes under X-ray radiation show that devices with high acceptor concentrations experience a significant decrease in open-circuit voltage and fill factor due to radiation, while devices with low acceptor concentrations are more resistant to these changes. The findings provide a quantitative understanding and physical model of the degradation mechanism.
Boosting Photocatalytic Activity Using Carbon Nitride Based 2D/2D van der Waa...Pawan Kumar
The surging demand for energy and staggering pollutants in the environment have geared the scientific community to explore sustainable pathways that are economically feasible and environmentally compelling. In this context, harnessing solar energy using semiconductor materials to generate charge pairs to drive photoredox reactions has been envisioned as a futuristic approach. Numerous inorganic crystals with promising nanoregime properties investigated in the past decade have yet to demonstrate practical application due to limited photon absorption and sluggish charge separation kinetics. Two-dimensional semiconductors with tunable optical and electronic properties and quasi-resistance-free lateral charge transfer mechanisms have shown great promise in photocatalysis. Polymeric graphitic carbon nitride (g-C3N4) is among the most promising candidates due to fine-tuned band edges and the feasibility of optimizing the optical properties via materials genomics. Constructing a two-dimensional (2D)/2D van der Waals (vdW) heterojunction by allies of 2D carbon nitride sheets and other 2D semiconductors has demonstrated enhanced charge separation with improved visible photon absorption, and the performance is not restricted by the lattice matching of constituting materials. With the advent of new 2D semiconductors over the recent past, the 2D/2D heterojunction assemblies are gaining momentum to design high performance photocatalysts for numerous applications. This review aims to highlight recent advancements and key understanding in carbon nitride based 2D/2D heterojunctions and their applications in photocatalysis, including small molecules activation, conversion, and degradations. We conclude with a forward-looking perspective discussing the key challenges and opportunity areas for future research.
IRJET - Advances in Perovskite Solar CellsIRJET Journal
This document summarizes recent advances in perovskite solar cells. It discusses how perovskite solar cell efficiency has rapidly increased from 3.8% in 2009 to over 24.2% today, catching up to silicon solar cells. The stability of perovskite structures depends on factors like ionicity and tolerance factor. While perovskite solar cells still face stability issues with water and temperature, encapsulation and tandem cell designs with silicon are helping to address this. Research is ongoing to improve materials, device architectures and manufacturing techniques to further increase efficiency and commercial viability of these promising thin film solar cells.
Photo-assisted oxidation of thiols to disulfides using cobalt ‘‘Nanorust’’ un...Pawan Kumar
Heterogeneous ‘‘Nanorust’’ containing cobalt oxide has been developed for the visible light assisted
oxidation of thiols to disulfides using molecular oxygen as an oxidant under alkaline free conditions and
therefore more environmentally friendly. Pyrolysis of heterogenized tetrasulfonated cobalt(II) phthalocyanine
(CoPcS) supported on mesoporous ceria (CeO2) transforms it into a novel heterogeneous ‘‘Nanorust’’
containing CoOx-C,N@CeO2 which exhibited higher catalytic activity than the homogeneous CoPcS as well
as the ceria immobilized CoPcS catalyst. Importantly, these catalysts could easily be recovered and recycled
for several runs, which makes the process greener and cost-effective.
1) The document describes the development of a new oxynitride-based phosphor called Y10Al2Si3O18N4:Re3+ (YAlSiON:Re3+) that can efficiently convert near-UV light from LEDs into blue, green, and orange colors.
2) By controlling the composition, the phosphor can produce tricolor emission without reabsorption of green and orange light in the blue region.
3) Energy transfer mechanisms allow production of blue light from Ce3+, green light from Ce3+-Tb3+ transfer, and orange light from Ce3+ → Tb3+ → Eu3+ transfer, enabling full-color emission from a
Heterostructured nanocomposite tin phthalocyanine@mesoporous ceria (SnPc@CeO2...Pawan Kumar
Heterostructured tin phthalocyanine supported to mesoporous ceria was synthesized and used a
photocatalyst for CO2 reduction under visible light. The photoreduction CO2 activities of the
heterostructures were investigated in the presence of triethylamine as sacrificial agent. The developed
photocatalyst exhibited high catalytic activity for photoreduction of CO2 and after 24 hours of visible
light irradiation 2342 mmol g1 cat of methanol (fMeOH ¼ 0.0223 or 2.23%) and 840 mmol g1 cat of CO
(fCO ¼ 0.0026 or 0.26%) were obtained as the major reaction products. The methanol formation rate
(RMeOH) and CO formation rate (RCO) was found to be 97.5 mmol h1 g1 cat and 35.0 mmol h1 g1 cat
respectively. While under the identical experimental conditions mesoporous ceria (meso-CeO2) gave
only 316 mmol g1 cat of methanol (fMeOH ¼ 0.003 or 0.30%) and 126 mmol g1 cat CO (fCO ¼ 0.0004
or 0.04%) with product formation rate RMeOH ¼ 13.2 mmol h1 g1 cat and RCO ¼ 5.3 mmol h1 g1 cat.
Furthermore, the recovered catalyst showed consistent catalytic activity for at least five runs without any
significant loss in product yields
Polymeric carbon nitride-based photocatalysts for photoreforming of biomass d...Pawan Kumar
Photoreforming of biomass to value-added chemicals and fuels is a chemical approach to extract photosynthetically-trapped energy in complex biomolecules which otherwise disintegrate naturally in the environment. Designing precise photocatalytic materials that can selectively break the sturdy, nature-designed biomass with multiplex chemical composition/bonding and inaccessible sites is central to deploying this technology. Polymeric carbon nitride (CN) comprised of a 2D network of condensed heptazine/triazine (C6N7/C3N3) core has shown great promise for photoreforming of biomass derivatives due to intriguing physicochemical and optical properties. This review comprehensively summarizes the state-of-the-art applications of CN-based photocatalysts for the conversion of lignocellulosic biomass derivatives. Various chemical and structural modifications in CN structure such as doping, surface functionalization, hybridization entailing to higher selectivity and conversion have been discussed aiming at providing valuable guidance for future CN-based materials design.
This document discusses X-ray diffraction (XRD) spectroscopy and provides examples of applying XRD principles to characterize different materials. It describes the basic principles of how XRD works using Bragg's law and Miller indices to identify crystal planes. Examples are given for characterizing silver nanoparticles, graphite, graphene oxide, and zinc oxide nanoparticles using XRD, including estimating particle sizes from XRD peak widths and identifying functional groups from infrared spectroscopy. References are also provided for further reading.
This research summary describes the work of Yong-Siou Chen focusing on developing nanomaterials for efficient light energy conversion applications. Two major projects are described: (1) Using thiolate-protected gold nanoclusters as a new class of photosensitizer for solar cells and hydrogen production from water splitting, achieving higher efficiencies than existing technologies. (2) Designing a tandem device using bismuth vanadate and lead halide perovskite solar cells for bias-free hydrogen production from water splitting under sunlight. The work establishes new nanomaterials and device architectures for clean, cost-effective electricity and hydrogen generation.
Nanostructured composite materials for CO2 activationPawan Kumar
This document discusses nanostructured composite materials for CO2 activation, specifically for the photocatalytic reduction of CO2 to valuable products. It provides background on the increasing energy crisis and climate change caused by fossil fuel use. It then summarizes the basic principles and challenges of using semiconductor photocatalysts for CO2 reduction, including appropriate band gap positions and preventing electron-hole recombination. The document discusses various approaches to overcoming these challenges, such as forming heterojunction composites and using co-catalysts to facilitate charge separation and transfer.
Organometal halide perovskite solar cells: Degradation and stabilityTaame Abraha Berhe
Organometal halide perovskite solar cells have evolved in an exponential manner in the two key areas of
efficiency and stability. The power conversion efficiency (PCE) reached 20.1% late last year. The key disquiet
was stability, which has been limiting practical application, but now the state of the art is promising, being
measured in thousands of hours. These improvements have been achieved through the application of
different materials, interfaces and device architecture optimizations, especially after the investigation of hole
conductor free mesoporous devices incorporating carbon electrodes, which promise stable, low cost
and easy device fabrication methods. However, this work is still far from complete.
Advantages and problems of perovskite solar cellalfachemistry
This article mainly introduces the advantages and problems of perovskite solar cell. Visit https://www.alfa-chemistry.com/products/perovskite-solar-cells-139.htm for more information.
Flexible and Ultrasoft Inorganic 1D Semiconductor and Heterostructure Systems...Pawan Kumar
Low dimensionality and high flexibility are key demands for flexible electronic semiconductor devices. SnIP, the first atomic-scale double helical semiconductor combines structural anisotropy and robustness with exceptional electronic properties. The benefit of the double helix, combined with a diverse structure on the nanoscale, ranging from strong covalent bonding to weak van der Waals interactions, and the large structure and property anisotropy offer substantial potential for applications in energy conversion and water splitting. It represents the next logical step in downscaling the inorganic semiconductors from classical 3D systems, via 2D semiconductors like MXenes or transition metal dichalcogenides, to the first downsizeable, polymer-like atomic-scale 1D semiconductor SnIP. SnIP shows intriguing mechanical properties featuring a bulk modulus three times lower than any IV, III-V, or II-VI semiconductor. In situ bending tests substantiate that pure SnIP fibers can be bent without an effect on their bonding properties. Organic and inorganic hybrids are prepared illustrating that SnIP is a candidate to fabricate flexible 1D composites for energy conversion and water splitting applications. SnIP@C3N4 hybrid forms an unusual soft material core–shell topology with graphenic carbon nitride wrapping around SnIP. A 1D van der Waals heterostructure is formed capable of performing effective water splitting.
Structure, Morphology & Infrared Spectroscopic Characterization of Ga (2x+2) ...IOSR Journals
This document summarizes a study that characterized the structure, morphology, and infrared spectroscopic properties of Ga(2x+2)NFe2(49-x)O3 ferrite synthesized using the sol gel technique. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used to analyze the size, type of bonding, and surface properties between the compounds. The results agreed with previous literature. GaN was used as a dopant for x=1 and x=5 in the formula to introduce its semiconducting properties into the ferrite system and study the effects.
Remarkable self-organization and unusual conductivity behavior in cellulose n...Pawan Kumar
Aqueous suspensions of cellulose nanocrystals were blended with Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) [PEDOT:PSS], and cast into thin films. The morphology, structure and electrical properties of the resulting nanocomposite thin films were thoroughly characterized. We found that the CNC–PEDOT:PSS blends self-organize into a layered vertical stack with a pitch of 100–200 nm while retaining a continuous percolation network for PEDOT. Atomic force microscopy, dynamic light scattering and multi-angle light scattering measurements confirmed the wrapping of polymer chains around the rod-like CNCs. The blended films exhibited improved molecular ordering of the PEDOT chains with concomitant improvement in the carrier mobility. The remarkable self-organization and enhanced structural order enabled the CNC–PEDOT:PSS blends to exhibit a high conductivity typical of PEDOT:PSS even when the content of the insulating CNCs in the nanocomposite was as high as 50 wt%.
This document proposes designing metal organic frameworks (MOFs) that can reversibly bind ethylene to purify it more efficiently than current energy-intensive distillation methods. MOFs with electrochemically active nickel-bisdithiolene complexes may allow voltage-driven capture and release of ethylene. Increasing the size and electron density of the aromatic backbone in these complexes could improve ethylene binding kinetics and efficiency by increasing porosity and decreasing the activation energy for electrochemical reactions. The document reports successful synthesis of HTTP-based MOFs with different metal centers and characterization of their nanostructures on graphite surfaces.
This document is a resume for Dr. Elena A. Guliants seeking a research or program management position involving renewable and alternative energy technologies. She has over 23 years of experience in fields such as photovoltaics, energy storage, hydrogen generation, and nanoenergetics. Her educational background includes a Ph.D. in Electrical Engineering and an M.B.A. She is fluent in English and Russian.
Water-splitting photoelectrodes consisting of heterojunctions of carbon nitri...Pawan Kumar
Quinary and senary non-stoichiometric double perovskites such as Ba2Ca0.66Nb1.34−xFexO6−δ (BCNF) have been utilized for gas sensing, solid oxide fuel cells and thermochemical CO2 reduction. Herein, we examined their potential as narrow bandgap semiconductors for use in solar energy harvesting. A cobalt co-doped BCNF, Ba2Ca0.66Nb0.68Fe0.33Co0.33O6−δ (BCNFCo), exhibited an optical absorption edge at ∼800 nm, p-type conduction and a distinct photoresponse up to 640 nm while demonstrating high thermochemical stability. A nanocomposite of BCNFCo and g-C3N4 (CN) was prepared via a facile solvent-assisted exfoliation/blending approach using dichlorobenzene and glycerol at a moderate temperature. The exfoliation of g-C3N4 followed by wrapping on perovskite established an effective heterojunction between the materials for charge separation. The conjugated 2D sheets of CN enabled better charge migration resulting in increased photoelectrochemical performance. A blend composed of 40 wt% perovskites and CN performed optimally, whilst achieving a photocurrent density as high as 1.5 mA cm−2 for sunlight-driven water-splitting with a Faradaic efficiency as high as ∼88%.
The document summarizes the educational background and research of Nishith Verma. It describes his B.Tech from Kanpur in 2009, M.Tech from Rourkela in 2011, and Ph.D from IIT Kanpur in chemical engineering under Professor Nishith Verma. It then outlines Verma's research developing polymer nanocomposites functionalized with nanoparticles and carbon nanofibers for environmental and energy applications. Some key contributions include developing methods to incorporate nanoparticles in-situ during polymerization for stable dispersion and exposure, and using carbon nanofibers to enhance mechanical, electrical, and thermal properties. Verma has several related patents and publications on using these materials for water treatment, antibacterial
New Materials Based on Acridine: Correlation Structure – Properties and Optoelectronic Applications
Original Research Article
Journal of Chemistry and Materials Research Vol. 1 (4), 2014, 112–122
Hayat Sadki, Samir Chtita, Mohammed Naciri Bennani, Tahar Lakhlifi, Mohammed Bouachrine*
Synthesis and Characterization of MOF based Composites for Energy storage app...Danyal Hakeem Jokhio
Despite extensive efforts and research put in the field, conventional energy storage devices (ESDs) such as various supercapacitors and batteries are near their performance limit in terms of power densities, energy densities, capacitance, charge retention, and cyclic stability. This is primarily due to limiting intrinsic properties of the electrode materials such as average surface area and poor porosity, combined with sluggish redox kinetics due to lack of electrode functionality. So, the need of the hour is to explore new materials for efficient storage of the energy. Among these new materials, metal-organic frameworks (MOFs) can serve as potential candidates because they have high specific surface area, high porosity with tuneable morphology and hence tuneable pore size, functionality linking to active metal sites and ligands. However, there remains a gap in fully utilising MOFs in energy storage applications commercially. Due to the highly porous nature of MOFs, their structural stability is compromised especially in aqueous electrolytes. To utilize the maximum potential of MOFs as electrode materials, it is of utmost importance to address poor structural integrity and low intrinsic conductivity of MOFs.
In this work, it has been tried to overcome the above-mentioned drawbacks of MOFs by using additives of conductive nature such as graphene nanoplatelets (GNP). Hydrothermal approach was used to synthesize hybrid MOF by controlling molar ratio of Nickel and Cobalt in combination with different organic ligands. As a battery-type supercapacitor electrode material, the 2:1 Ni/Co hybrid MOF with 40mg GNP, using terephthalic acid as ligand, delivered a high specific capacity of 658.8 C·g−1 at the current density of 1 A·g−1. Similarly, the 1:2 Ni/Co hybrid MOF, using 2-MethylImidazole as ligand, delivered a high specific capacity of 642.4 C·g−1 at the current density of 1 A·g−1. Moreover, breakthrough results were obtained by optimizing synthesis with in-situ deposition on nickel foam of 2:1 Ni/Co (with 40mg GNP) hybrid MOF, which produced an impressive specific capacity of 1264 C·g−1 at 1 A/g, surpassing, to the best of our knowledge, most of the previously reported MOF based electrode materials.
This work not only develops a high-performance electrode material of supercapacitor, but being the first of its kind in Pakistan, also provides the foundation of systematic research for the electrochemical properties of multi-metal MOFs.
Polymeric carbon nitride-based photocatalysts for photoreforming of biomass d...Pawan Kumar
Photoreforming of biomass to value-added chemicals and fuels is a chemical approach to extract photosynthetically-trapped energy in complex biomolecules which otherwise disintegrate naturally in the environment. Designing precise photocatalytic materials that can selectively break the sturdy, nature-designed biomass with multiplex chemical composition/bonding and inaccessible sites is central to deploying this technology. Polymeric carbon nitride (CN) comprised of a 2D network of condensed heptazine/triazine (C6N7/C3N3) core has shown great promise for photoreforming of biomass derivatives due to intriguing physicochemical and optical properties. This review comprehensively summarizes the state-of-the-art applications of CN-based photocatalysts for the conversion of lignocellulosic biomass derivatives. Various chemical and structural modifications in CN structure such as doping, surface functionalization, hybridization entailing to higher selectivity and conversion have been discussed aiming at providing valuable guidance for future CN-based materials design.
1D Nanomaterials: Design, Synthesis, and Applications in Sodium–Ion BatteriesBilal Qadir
This document reviews 1D nanomaterials and their applications in sodium-ion batteries (SIBs). 1D nanomaterials such as nanofibers, nanotubes, nanorods, and nanowires are promising electrode materials for SIBs due to their uniform structure, oriented ion and electron transport, and ability to tolerate stress changes. The document discusses various synthetic methods for producing 1D nanomaterials, including electrospinning, gas-phase routes, solution-phase routes, and template-assisted methods. It also examines how different morphologies and structural features of 1D nanomaterials can affect electrochemical properties in SIBs. Finally, the document outlines challenges in fabricating 1D nanomaterials and prospects for their future use in
Development of novel catalytic systems for photoreduction of CO2 to fuel and ...Pawan Kumar
This document summarizes the proposed research project on developing novel catalytic systems for the photoreduction of CO2 to fuels and chemicals. The project will focus on using transition metal complexes as photocatalysts immobilized on supporting materials like graphene oxide. Previous work has shown that ruthenium and cobalt complexes immobilized on graphene oxide are effective visible-light active catalysts for reducing CO2 to methanol. The proposed work will synthesize new graphene oxide-supported transition metal complexes and characterize their photocatalytic activity for CO2 reduction.
1) Mn3O4 nanoparticles were anchored onto graphene nanosheets through a simple ultrasound-assisted synthesis at room temperature to create a nanocomposite for use as a supercapacitor electrode.
2) Characterization showed the Mn3O4 nanoparticles were uniformly 4-8 nm in size and anchored on the graphene nanosheets.
3) Electrochemical testing found the nanocomposite exhibited a high specific capacitance of 312 F/g, approximately three times that of pristine Mn3O4, and maintained 76% of its capacitance after 1000 charge/discharge cycles.
TiO2-HfN Radial Nano-Heterojunction: A Hot Carrier Photoanode for Sunlight-Dr...Pawan Kumar
The lack of active, stable, earth-abundant, and visible-light absorbing materials to replace
plasmonic noble metals is a critical obstacle for researchers in developing highly efficient and costeffective photocatalytic systems. Herein, a core–shell nanotube catalyst was fabricated consisting of
atomic layer deposited HfN shell and anodic TiO2 support layer with full-visible regime photoactivity
for photoelectrochemical water splitting. The HfN active layer has two unique characteristics: (1) a
large bandgap between optical and acoustic phonon modes (2) and no electronic bandgap, which
allows a large population of long life-time hot carriers, which are used to enhance the photoelectrochemical performance. The photocurrent density (≈2.5 mA·cm−2 at 1 V vs. Ag/AgCl) obtained in
this study under AM 1.5G 1 Sun illumination is unprecedented, as it is superior to most existing
plasmonic noble metal-decorated catalysts and surprisingly indicates a photocurrent response that
extends to 730 nm. The result demonstrates the far-reaching application potential of replacing active
HER/HOR noble metals such as Au, Ag, Pt, Pd, etc. with low-cost plasmonic ceramics.
This document summarizes research on improving the stability of perovskite solar cells. It discusses using tin instead of lead in perovskite materials to reduce toxicity. A carbon and epoxy electrode is also proposed to improve moisture stability. Test results show the carbon-epoxy electrode maintains solar cell efficiency for over 20 days in humid conditions, while a carbon-only device degrades after 16 days. Coating the carbon-epoxy with silver further enhances moisture resistance and electrical conductivity.
IRJET- Optical Properties of Copper Oxides (CuO) and Titanium Oxides (TiO2) N...IRJET Journal
This document discusses the optical properties of copper oxide (CuO) and titanium oxide (TiO2) nanoparticles for use in solar thermal systems. It investigates the nanoparticles' absorption, scattering, and extinction coefficients using Rayleigh's scattering model. The results show that CuO nanoparticles have high absorption and scattering coefficients in the UV range of 200-500nm wavelengths. While scattering decreases above 500nm, absorption remains significant, leading to high total extinction coefficients across the solar spectrum for CuO nanoparticles suspended at concentrations of 2PPM, 4PPM, and 6PPM.
This research summary describes the work of Yong-Siou Chen focusing on developing nanomaterials for efficient light energy conversion applications. Two major projects are described: (1) Using thiolate-protected gold nanoclusters as a new class of photosensitizer for solar cells and hydrogen production from water splitting, achieving higher efficiencies than existing technologies. (2) Designing a tandem device using bismuth vanadate and lead halide perovskite solar cells for bias-free hydrogen production from water splitting under sunlight. The work establishes new nanomaterials and device architectures for clean, cost-effective electricity and hydrogen generation.
Nanostructured composite materials for CO2 activationPawan Kumar
This document discusses nanostructured composite materials for CO2 activation, specifically for the photocatalytic reduction of CO2 to valuable products. It provides background on the increasing energy crisis and climate change caused by fossil fuel use. It then summarizes the basic principles and challenges of using semiconductor photocatalysts for CO2 reduction, including appropriate band gap positions and preventing electron-hole recombination. The document discusses various approaches to overcoming these challenges, such as forming heterojunction composites and using co-catalysts to facilitate charge separation and transfer.
Organometal halide perovskite solar cells: Degradation and stabilityTaame Abraha Berhe
Organometal halide perovskite solar cells have evolved in an exponential manner in the two key areas of
efficiency and stability. The power conversion efficiency (PCE) reached 20.1% late last year. The key disquiet
was stability, which has been limiting practical application, but now the state of the art is promising, being
measured in thousands of hours. These improvements have been achieved through the application of
different materials, interfaces and device architecture optimizations, especially after the investigation of hole
conductor free mesoporous devices incorporating carbon electrodes, which promise stable, low cost
and easy device fabrication methods. However, this work is still far from complete.
Advantages and problems of perovskite solar cellalfachemistry
This article mainly introduces the advantages and problems of perovskite solar cell. Visit https://www.alfa-chemistry.com/products/perovskite-solar-cells-139.htm for more information.
Flexible and Ultrasoft Inorganic 1D Semiconductor and Heterostructure Systems...Pawan Kumar
Low dimensionality and high flexibility are key demands for flexible electronic semiconductor devices. SnIP, the first atomic-scale double helical semiconductor combines structural anisotropy and robustness with exceptional electronic properties. The benefit of the double helix, combined with a diverse structure on the nanoscale, ranging from strong covalent bonding to weak van der Waals interactions, and the large structure and property anisotropy offer substantial potential for applications in energy conversion and water splitting. It represents the next logical step in downscaling the inorganic semiconductors from classical 3D systems, via 2D semiconductors like MXenes or transition metal dichalcogenides, to the first downsizeable, polymer-like atomic-scale 1D semiconductor SnIP. SnIP shows intriguing mechanical properties featuring a bulk modulus three times lower than any IV, III-V, or II-VI semiconductor. In situ bending tests substantiate that pure SnIP fibers can be bent without an effect on their bonding properties. Organic and inorganic hybrids are prepared illustrating that SnIP is a candidate to fabricate flexible 1D composites for energy conversion and water splitting applications. SnIP@C3N4 hybrid forms an unusual soft material core–shell topology with graphenic carbon nitride wrapping around SnIP. A 1D van der Waals heterostructure is formed capable of performing effective water splitting.
Structure, Morphology & Infrared Spectroscopic Characterization of Ga (2x+2) ...IOSR Journals
This document summarizes a study that characterized the structure, morphology, and infrared spectroscopic properties of Ga(2x+2)NFe2(49-x)O3 ferrite synthesized using the sol gel technique. X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared spectroscopy (FTIR) were used to analyze the size, type of bonding, and surface properties between the compounds. The results agreed with previous literature. GaN was used as a dopant for x=1 and x=5 in the formula to introduce its semiconducting properties into the ferrite system and study the effects.
Remarkable self-organization and unusual conductivity behavior in cellulose n...Pawan Kumar
Aqueous suspensions of cellulose nanocrystals were blended with Poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) [PEDOT:PSS], and cast into thin films. The morphology, structure and electrical properties of the resulting nanocomposite thin films were thoroughly characterized. We found that the CNC–PEDOT:PSS blends self-organize into a layered vertical stack with a pitch of 100–200 nm while retaining a continuous percolation network for PEDOT. Atomic force microscopy, dynamic light scattering and multi-angle light scattering measurements confirmed the wrapping of polymer chains around the rod-like CNCs. The blended films exhibited improved molecular ordering of the PEDOT chains with concomitant improvement in the carrier mobility. The remarkable self-organization and enhanced structural order enabled the CNC–PEDOT:PSS blends to exhibit a high conductivity typical of PEDOT:PSS even when the content of the insulating CNCs in the nanocomposite was as high as 50 wt%.
This document proposes designing metal organic frameworks (MOFs) that can reversibly bind ethylene to purify it more efficiently than current energy-intensive distillation methods. MOFs with electrochemically active nickel-bisdithiolene complexes may allow voltage-driven capture and release of ethylene. Increasing the size and electron density of the aromatic backbone in these complexes could improve ethylene binding kinetics and efficiency by increasing porosity and decreasing the activation energy for electrochemical reactions. The document reports successful synthesis of HTTP-based MOFs with different metal centers and characterization of their nanostructures on graphite surfaces.
This document is a resume for Dr. Elena A. Guliants seeking a research or program management position involving renewable and alternative energy technologies. She has over 23 years of experience in fields such as photovoltaics, energy storage, hydrogen generation, and nanoenergetics. Her educational background includes a Ph.D. in Electrical Engineering and an M.B.A. She is fluent in English and Russian.
Water-splitting photoelectrodes consisting of heterojunctions of carbon nitri...Pawan Kumar
Quinary and senary non-stoichiometric double perovskites such as Ba2Ca0.66Nb1.34−xFexO6−δ (BCNF) have been utilized for gas sensing, solid oxide fuel cells and thermochemical CO2 reduction. Herein, we examined their potential as narrow bandgap semiconductors for use in solar energy harvesting. A cobalt co-doped BCNF, Ba2Ca0.66Nb0.68Fe0.33Co0.33O6−δ (BCNFCo), exhibited an optical absorption edge at ∼800 nm, p-type conduction and a distinct photoresponse up to 640 nm while demonstrating high thermochemical stability. A nanocomposite of BCNFCo and g-C3N4 (CN) was prepared via a facile solvent-assisted exfoliation/blending approach using dichlorobenzene and glycerol at a moderate temperature. The exfoliation of g-C3N4 followed by wrapping on perovskite established an effective heterojunction between the materials for charge separation. The conjugated 2D sheets of CN enabled better charge migration resulting in increased photoelectrochemical performance. A blend composed of 40 wt% perovskites and CN performed optimally, whilst achieving a photocurrent density as high as 1.5 mA cm−2 for sunlight-driven water-splitting with a Faradaic efficiency as high as ∼88%.
The document summarizes the educational background and research of Nishith Verma. It describes his B.Tech from Kanpur in 2009, M.Tech from Rourkela in 2011, and Ph.D from IIT Kanpur in chemical engineering under Professor Nishith Verma. It then outlines Verma's research developing polymer nanocomposites functionalized with nanoparticles and carbon nanofibers for environmental and energy applications. Some key contributions include developing methods to incorporate nanoparticles in-situ during polymerization for stable dispersion and exposure, and using carbon nanofibers to enhance mechanical, electrical, and thermal properties. Verma has several related patents and publications on using these materials for water treatment, antibacterial
New Materials Based on Acridine: Correlation Structure – Properties and Optoelectronic Applications
Original Research Article
Journal of Chemistry and Materials Research Vol. 1 (4), 2014, 112–122
Hayat Sadki, Samir Chtita, Mohammed Naciri Bennani, Tahar Lakhlifi, Mohammed Bouachrine*
Synthesis and Characterization of MOF based Composites for Energy storage app...Danyal Hakeem Jokhio
Despite extensive efforts and research put in the field, conventional energy storage devices (ESDs) such as various supercapacitors and batteries are near their performance limit in terms of power densities, energy densities, capacitance, charge retention, and cyclic stability. This is primarily due to limiting intrinsic properties of the electrode materials such as average surface area and poor porosity, combined with sluggish redox kinetics due to lack of electrode functionality. So, the need of the hour is to explore new materials for efficient storage of the energy. Among these new materials, metal-organic frameworks (MOFs) can serve as potential candidates because they have high specific surface area, high porosity with tuneable morphology and hence tuneable pore size, functionality linking to active metal sites and ligands. However, there remains a gap in fully utilising MOFs in energy storage applications commercially. Due to the highly porous nature of MOFs, their structural stability is compromised especially in aqueous electrolytes. To utilize the maximum potential of MOFs as electrode materials, it is of utmost importance to address poor structural integrity and low intrinsic conductivity of MOFs.
In this work, it has been tried to overcome the above-mentioned drawbacks of MOFs by using additives of conductive nature such as graphene nanoplatelets (GNP). Hydrothermal approach was used to synthesize hybrid MOF by controlling molar ratio of Nickel and Cobalt in combination with different organic ligands. As a battery-type supercapacitor electrode material, the 2:1 Ni/Co hybrid MOF with 40mg GNP, using terephthalic acid as ligand, delivered a high specific capacity of 658.8 C·g−1 at the current density of 1 A·g−1. Similarly, the 1:2 Ni/Co hybrid MOF, using 2-MethylImidazole as ligand, delivered a high specific capacity of 642.4 C·g−1 at the current density of 1 A·g−1. Moreover, breakthrough results were obtained by optimizing synthesis with in-situ deposition on nickel foam of 2:1 Ni/Co (with 40mg GNP) hybrid MOF, which produced an impressive specific capacity of 1264 C·g−1 at 1 A/g, surpassing, to the best of our knowledge, most of the previously reported MOF based electrode materials.
This work not only develops a high-performance electrode material of supercapacitor, but being the first of its kind in Pakistan, also provides the foundation of systematic research for the electrochemical properties of multi-metal MOFs.
Polymeric carbon nitride-based photocatalysts for photoreforming of biomass d...Pawan Kumar
Photoreforming of biomass to value-added chemicals and fuels is a chemical approach to extract photosynthetically-trapped energy in complex biomolecules which otherwise disintegrate naturally in the environment. Designing precise photocatalytic materials that can selectively break the sturdy, nature-designed biomass with multiplex chemical composition/bonding and inaccessible sites is central to deploying this technology. Polymeric carbon nitride (CN) comprised of a 2D network of condensed heptazine/triazine (C6N7/C3N3) core has shown great promise for photoreforming of biomass derivatives due to intriguing physicochemical and optical properties. This review comprehensively summarizes the state-of-the-art applications of CN-based photocatalysts for the conversion of lignocellulosic biomass derivatives. Various chemical and structural modifications in CN structure such as doping, surface functionalization, hybridization entailing to higher selectivity and conversion have been discussed aiming at providing valuable guidance for future CN-based materials design.
1D Nanomaterials: Design, Synthesis, and Applications in Sodium–Ion BatteriesBilal Qadir
This document reviews 1D nanomaterials and their applications in sodium-ion batteries (SIBs). 1D nanomaterials such as nanofibers, nanotubes, nanorods, and nanowires are promising electrode materials for SIBs due to their uniform structure, oriented ion and electron transport, and ability to tolerate stress changes. The document discusses various synthetic methods for producing 1D nanomaterials, including electrospinning, gas-phase routes, solution-phase routes, and template-assisted methods. It also examines how different morphologies and structural features of 1D nanomaterials can affect electrochemical properties in SIBs. Finally, the document outlines challenges in fabricating 1D nanomaterials and prospects for their future use in
Development of novel catalytic systems for photoreduction of CO2 to fuel and ...Pawan Kumar
This document summarizes the proposed research project on developing novel catalytic systems for the photoreduction of CO2 to fuels and chemicals. The project will focus on using transition metal complexes as photocatalysts immobilized on supporting materials like graphene oxide. Previous work has shown that ruthenium and cobalt complexes immobilized on graphene oxide are effective visible-light active catalysts for reducing CO2 to methanol. The proposed work will synthesize new graphene oxide-supported transition metal complexes and characterize their photocatalytic activity for CO2 reduction.
1) Mn3O4 nanoparticles were anchored onto graphene nanosheets through a simple ultrasound-assisted synthesis at room temperature to create a nanocomposite for use as a supercapacitor electrode.
2) Characterization showed the Mn3O4 nanoparticles were uniformly 4-8 nm in size and anchored on the graphene nanosheets.
3) Electrochemical testing found the nanocomposite exhibited a high specific capacitance of 312 F/g, approximately three times that of pristine Mn3O4, and maintained 76% of its capacitance after 1000 charge/discharge cycles.
TiO2-HfN Radial Nano-Heterojunction: A Hot Carrier Photoanode for Sunlight-Dr...Pawan Kumar
The lack of active, stable, earth-abundant, and visible-light absorbing materials to replace
plasmonic noble metals is a critical obstacle for researchers in developing highly efficient and costeffective photocatalytic systems. Herein, a core–shell nanotube catalyst was fabricated consisting of
atomic layer deposited HfN shell and anodic TiO2 support layer with full-visible regime photoactivity
for photoelectrochemical water splitting. The HfN active layer has two unique characteristics: (1) a
large bandgap between optical and acoustic phonon modes (2) and no electronic bandgap, which
allows a large population of long life-time hot carriers, which are used to enhance the photoelectrochemical performance. The photocurrent density (≈2.5 mA·cm−2 at 1 V vs. Ag/AgCl) obtained in
this study under AM 1.5G 1 Sun illumination is unprecedented, as it is superior to most existing
plasmonic noble metal-decorated catalysts and surprisingly indicates a photocurrent response that
extends to 730 nm. The result demonstrates the far-reaching application potential of replacing active
HER/HOR noble metals such as Au, Ag, Pt, Pd, etc. with low-cost plasmonic ceramics.
This document summarizes research on improving the stability of perovskite solar cells. It discusses using tin instead of lead in perovskite materials to reduce toxicity. A carbon and epoxy electrode is also proposed to improve moisture stability. Test results show the carbon-epoxy electrode maintains solar cell efficiency for over 20 days in humid conditions, while a carbon-only device degrades after 16 days. Coating the carbon-epoxy with silver further enhances moisture resistance and electrical conductivity.
IRJET- Optical Properties of Copper Oxides (CuO) and Titanium Oxides (TiO2) N...IRJET Journal
This document discusses the optical properties of copper oxide (CuO) and titanium oxide (TiO2) nanoparticles for use in solar thermal systems. It investigates the nanoparticles' absorption, scattering, and extinction coefficients using Rayleigh's scattering model. The results show that CuO nanoparticles have high absorption and scattering coefficients in the UV range of 200-500nm wavelengths. While scattering decreases above 500nm, absorption remains significant, leading to high total extinction coefficients across the solar spectrum for CuO nanoparticles suspended at concentrations of 2PPM, 4PPM, and 6PPM.
Design and Simulation of Dye Sensitized Solar Cell as a Cost-Effective Alt...Scientific Review SR
The continuous research in the area of renewable energy technology to substitute the unsustainable nature of fossil
fuel in terms of it future availability and negative environmental impact created by fossil fuel has ensure the explore
of solar energy as a good alternative. Dye sensitized solar cells (DSSCs) serve to be a good alternative means of
producing photovoltaic solar cell. This work reports the working principle and construction process of dye-sensitized
solar cell. A synthesized dye (Ruthenium oxide) and an iodide electrolyte were used for better performance based on
already researched work. Also, this work reports the evaluation process with results recorded by the produced solar
cell within 6:00am (GMT) and 6:00pm (GMT) for selected days. The results from the evaluation process show a
better performance of a dye-sensitized solar cell in low and normal sunny day. The solar cell has a good performance
at 12:00noon with a 0.5V output.
This document summarizes molecular dynamics simulations of radiation damage in zirconia (ZrO2) at energies ranging from 0.1-0.5 MeV. The simulations find that while zirconia is highly resistant to amorphization, there is still a large number of point defects and small defect clusters created by the radiation. However, these defects are isolated from each other, resulting in dilute damage that does not disrupt the long-range crystalline structure. The simulations quantify the number of displacements and defects over time and find that electronic energy losses play an important role in the damage evolution. The findings have implications for using zirconia in nuclear waste storage by suggesting radiation can create many point defects even while
Organic solar cells the exciting interplay of excitons and nano-morphologyvvgk-thalluri
1) The document summarizes organic solar cells, which use a bulk heterojunction of a conjugated polymer donor and fullerene acceptor. When light is absorbed, excitons are formed that must dissociate at the donor-acceptor interface into free charges.
2) The bulk heterojunction morphology, consisting of an interpenetrating network of the donor and acceptor materials, allows more excitons to dissociate since the interface is throughout the volume. This leads to higher efficiencies than simple bilayer cells.
3) Efficiencies of over 6% have been achieved but further work is needed to improve stability and lower costs for organic solar cells to become commercially viable. Optimization of
Organic solar cells principles, mechanism and recent dvelopmentseSAT Publishing House
This document summarizes recent developments in organic solar cell technology. It discusses how organic solar cells work by generating electron-hole pairs called excitons when light is absorbed. Excitons must dissociate at donor-acceptor interfaces to generate free charges. There is ongoing research to better understand the mechanism of exciton dissociation. Computational methods like time-dependent density functional theory are being used to simulate charge transfer processes. Experimental research focuses on spectroscopic analysis to study conversion processes in picosecond timescales. Recent efficiency improvements and new device architectures are driving the commercial potential of organic solar cells.
IRJET- Black Phosphorous as an Alternative to Current Semiconductor MaterialsIRJET Journal
Black phosphorus (BP) is being explored as an alternative semiconductor material to silicon and graphene due to its high carrier mobility, tunable bandgap, and potential for applications in flexible electronics and internet of things devices. BP has shown carrier mobilities over 10,000 cm2/V∙s, higher than silicon, as well as a bandgap that can be tuned by controlling the number of layers. While challenges remain around scalable production and material stability, BP shows promise as a competitor to silicon and ability to overcome limitations of graphene for semiconductor applications.
This document summarizes a presentation on using carbon nanotubes in solar panel technology. It discusses how carbon nanotubes can improve the efficiency of solar cells compared to traditional organic solar cells. Carbon nanotubes are classified as single-walled or multi-walled nanotubes. Carbon nanotubes and a polymer called MEH-PPV-CN are used as materials in constructing a carbon solar cell. The cell works by generating electrons when exposed to light, which are transferred between energy bands and build up voltage. Adding carbon nanotubes can increase the cell's efficiency by improving light absorption and electron transport. Potential applications include using carbon nanotubes in the photoactive layer or as transparent electrodes.
This document summarizes research into developing novel dye molecules containing ferrocene and BODIPY groups for use in dye-sensitized solar cells. The dyes were designed with an electron donor (ferrocene), pi-spacer (acetylene), and electron acceptor (BODIPY and cyanoacrylic acid) to encourage light absorption and charge separation. The dyes exhibited broad light absorption, reversible redox behavior, and a desirable shift of electron density from donor to acceptor when excited. While showing promise for solar energy applications, further testing of the dyes in solar cell devices is still needed to verify their performance.
Emerging Next Generation Solar Cells: Route to High Efficiency and Low Costijtsrd
Generation of clean energy is one of the main challenges of the 21st century. Solar energy is the most abundantly available renewable energy source which would be supplying more than 50% of the global electricity demand in 2100. Solar cells are used to convert light energy into electrical energy directly with an appeal that it does not generate any harmful bi-products, like greenhouse gasses. The manufacturing of solar cells is actually based on the types of semiconducting or non-semiconducting materials used and commercial maturity. From the very beginning of the terrestrial use of Solar Cells, efficiency and costs are the main focusing areas of research. The definition of so-called emerging technologies sometimes described as including any technology capable of overcoming the Shockley“Queisser limit of power conversion efficiency (33.7 percent) for a single junction device. In this paper, few promising materials for solar cells are discussed including their structural morphology, electrical and optical properties. The excellent state of the art technology, advantages and potential research issues yet to be explored are also pointed out. Md. Samiul Islam Sadek | Dr. M Junaebur Rashid | Dr. Zahid Hasan Mahmood"Emerging Next Generation Solar Cells: Route to High Efficiency and Low Cost" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-1 | Issue-4 , June 2017, URL: http://www.ijtsrd.com/papers/ijtsrd96.pdf http://www.ijtsrd.com/physics/other/96/emerging-next-generation-solar-cells-route-to-high-efficiency-and-low-cost/md-samiul-islam-sadek
The document discusses improving light trapping in perovskite solar cells by developing a nano-structured transparent contact. The goal is to enhance the quantum efficiency, short-circuit current, and open-circuit voltage of perovskite solar cells to increase overall efficiency. A methodology is proposed that involves simulating flat and nano-cone structured perovskite solar cells and modifying the nano-cone structure parameters to optimize light trapping. Simulation results show reduced power losses and reflections with the nano-cone structures compared to flat structures, demonstrating enhanced light trapping. Future work could involve developing lead-free perovskites and texturing multiple layers.
The document summarizes the fabrication, characterization, and performance evaluation of a dye-sensitized solar cell (DSSC). It was submitted as a project report by three students to fulfill their degree requirements in energy engineering at Central University of Jharkhand. The report provides background on DSSCs, describes the experimental methodology used to assemble a DSSC, and presents results and discussion of testing the fabricated DSSC. Key aspects covered include the use of TiO2 semiconductor, ruthenium dye sensitizer, carbon counter electrode, and testing under Ranchi, India weather conditions.
Multifunctional materials for clean energy conversionDevika Laishram
With the rapid depletion of fossil fuels, rising environmental concerns,
and population growth, it is inevitable to develop clean energy technologies
to power our future society [1e4]. These energy conversion and storage
technologies are anticipated to be sustainable and also capable of meeting
our long-term energy needs. During the past few years, extensive research
interests have been devoted to the advancement of energy conversion devices, as they play a crucial role in the prosperity and economic growth of
a country. Particularly, the energy conversion technologies such as solar
and fuel cells have proved to be highly reliable and can offer clean and sustainable energy at affordable rate [5e8]. However, the performance potential of these devices, such as output voltage, conversion efficiency, and
stability, are greatly relied on the materials used. The energy conversion process comprises physical and/or chemical reactions at th
High Efficiency and Thermal Stability A Downright Response to the Commerciali...ijtsrd
Organo metal halide perovskites represent a new paradigm for photovoltaics, possessing the propensity to overcome the performance limits of present technologies and achieve low cost and high efficiency and appreciable stability. Recently, efficiencies in excess of 22 has been recorded, but very little is known about their operational characteristics under thermal stress. This paper summarizes the research that focused on the achievements made in the field of perovskite photovoltaics, as well as the principal hurdles to the commercialization of perovskites. In this work, numerical modeling of the planar N I P architectural structure Glass SnO2 F TiO2 CH3NH3PbI3 Spiro OMeTAD Au of the Methylammonium Lead Iodide Perovskite Solar Cell was performed for the efficiency improvement of the solar cell. A promising result was achieved with Power Conversion Efficiency PCE of 29.31 , Fill Factor FF 82.63 , short circuit current density JSC 23.55 mA cm2 and open circuit voltage VOC 1.51 V. Simulation of the modeled perovskite solar cell was executed using Solar Cell Capacitance Simulator SCAPS 1D . At higher temperatures, the solar cell’s carrier concentration, band gaps, electron and hole mobilities were affected, thus the lower power conversion efficiency. In contrast to the nominal trend where recoded models have their best efficiencies at temperature measured in Kelvin, K 300K before consistently decreasing, it was observed that the Power Conversion Efficiency of this model appreciated above 300K hitting a peak efficiency of 29.3445 at 325K, maintained a high efficiency through 355K. The results presented will give a valuable guideline for the feasible fabrication and designing of thermally stable and high power conversion efficiency perovskite solar cells. Chisom Patrick Mbachu | Samuel Okechukwu Okozi | Eli Danladi "High Efficiency and Thermal Stability: A Downright Response to the Commercialization of Perovskite Solar Cells" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-7 | Issue-1 , February 2023, URL: https://www.ijtsrd.com/papers/ijtsrd52468.pdf Paper URL: https://www.ijtsrd.com/engineering/electrical-engineering/52468/high-efficiency-and-thermal-stability-a-downright-response-to-the-commercialization-of-perovskite-solar-cells/chisom-patrick-mbachu
Detection Methods That Use Signal Processing And Interfere...Claudia Brown
This document discusses fault detection methods for photovoltaic (PV) array systems. It begins with an abstract stating that PV power generation is an important research area due to high renewable energy demand. More research is needed to detect faults in PV arrays and systems to improve performance and availability. The paper then analyzes various fault detection methods that use signal processing and interfere with PV array analysis techniques. Finally, the conclusion discusses fault detection methods that use signal processing techniques.
Recent progress on reduced graphene oxide....suresh kannan
The document summarizes recent progress on using reduced graphene oxide (rGO)-based materials as counter electrodes for dye-sensitized solar cells (DSSCs) as a cost-effective alternative to platinum. It discusses how rGO on its own is not effective as a counter electrode but that adding metal nanoparticles to rGO composites improves their catalytic activity and performance in DSSCs. The document reviews various rGO composites that have been studied, including those with silver, nickel, tungsten and platinum nanoparticles, as well as metal oxides and dichalcogenides. It compares the photovoltaic parameters of DSSCs using these rGO composite counter electrodes to those using conventional platinum counter electrodes
An Research Article on Fabrication and Characterization of Nickel Oxide Coate...ijtsrd
In this paper we have produced NiO thin film based solar cells. The NiO thin film was then studied for their structural, optical and electrical properties. By the help of these results we have capable to know about the structure of NiO the phase purity of the thin film X ray diffraction XRD pattern of NiO showed the diffraction planes corresponding to cubic phase respectively. The optical properties showed that with the increase in the deposition time of NiO the energy band gap varied between 3.1 to 3.24 eV. In the end, IV characteristics of the thin films were obtained by the help of matlab in the presence of light as will as dark region. Vijay Aithekar "An Research Article on Fabrication and Characterization of Nickel Oxide Coated Solar Cell" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-3 | Issue-5 , August 2019, URL: https://www.ijtsrd.com/papers/ijtsrd25300.pdfPaper URL: https://www.ijtsrd.com/physics/nanotechnology/25300/an-research-article-on-fabrication-and-characterization-of-nickel-oxide-coated-solar-cell/vijay-aithekar
International Journal of Computational Engineering Research(IJCER) is an intentional online Journal in English monthly publishing journal. This Journal publish original research work that contributes significantly to further the scientific knowledge in engineering and Technology.
Perovskite solar cells - An Introduction, By Dawn John MullasseryDawn John Mullassery
Perovskite solar cells (PSCs) are a promising photovoltaic technology that has seen rapid increases in power conversion efficiency from 9.7% to over 20% in just a few years. PSCs offer advantages over other solar cell technologies in terms of cost of raw materials, fabrication, and efficiency. However, research is still needed to address challenges such as stability in the presence of moisture and the toxicity of lead used in early PSC designs. Future work aims to remove toxicity concerns and develop thin film and flexible PSC designs to enable widespread commercialization of this emerging solar technology.
Similar to Recent Advances in Photovoltaic Technology based on Perovskite Solar Cell- A Review (20)
TUNNELING IN HIMALAYAS WITH NATM METHOD: A SPECIAL REFERENCES TO SUNGAL TUNNE...IRJET Journal
1) The document discusses the Sungal Tunnel project in Jammu and Kashmir, India, which is being constructed using the New Austrian Tunneling Method (NATM).
2) NATM involves continuous monitoring during construction to adapt to changing ground conditions, and makes extensive use of shotcrete for temporary tunnel support.
3) The methodology section outlines the systematic geotechnical design process for tunnels according to Austrian guidelines, and describes the various steps of NATM tunnel construction including initial and secondary tunnel support.
STUDY THE EFFECT OF RESPONSE REDUCTION FACTOR ON RC FRAMED STRUCTUREIRJET Journal
This study examines the effect of response reduction factors (R factors) on reinforced concrete (RC) framed structures through nonlinear dynamic analysis. Three RC frame models with varying heights (4, 8, and 12 stories) were analyzed in ETABS software under different R factors ranging from 1 to 5. The results showed that displacement increased as the R factor decreased, indicating less linear behavior for lower R factors. Drift also decreased proportionally with increasing R factors from 1 to 5. Shear forces in the frames decreased with higher R factors. In general, R factors of 3 to 5 produced more satisfactory performance with less displacement and drift. The displacement variations between different building heights were consistent at different R factors. This study evaluated how R factors influence
A COMPARATIVE ANALYSIS OF RCC ELEMENT OF SLAB WITH STARK STEEL (HYSD STEEL) A...IRJET Journal
This study compares the use of Stark Steel and TMT Steel as reinforcement materials in a two-way reinforced concrete slab. Mechanical testing is conducted to determine the tensile strength, yield strength, and other properties of each material. A two-way slab design adhering to codes and standards is executed with both materials. The performance is analyzed in terms of deflection, stability under loads, and displacement. Cost analyses accounting for material, durability, maintenance, and life cycle costs are also conducted. The findings provide insights into the economic and structural implications of each material for reinforcement selection and recommendations on the most suitable material based on the analysis.
Effect of Camber and Angles of Attack on Airfoil CharacteristicsIRJET Journal
This document discusses a study analyzing the effect of camber, position of camber, and angle of attack on the aerodynamic characteristics of airfoils. Sixteen modified asymmetric NACA airfoils were analyzed using computational fluid dynamics (CFD) by varying the camber, camber position, and angle of attack. The results showed the relationship between these parameters and the lift coefficient, drag coefficient, and lift to drag ratio. This provides insight into how changes in airfoil geometry impact aerodynamic performance.
A Review on the Progress and Challenges of Aluminum-Based Metal Matrix Compos...IRJET Journal
This document reviews the progress and challenges of aluminum-based metal matrix composites (MMCs), focusing on their fabrication processes and applications. It discusses how various aluminum MMCs have been developed using reinforcements like borides, carbides, oxides, and nitrides to improve mechanical and wear properties. These composites have gained prominence for their lightweight, high-strength and corrosion resistance properties. The document also examines recent advancements in fabrication techniques for aluminum MMCs and their growing applications in industries such as aerospace and automotive. However, it notes that challenges remain around issues like improper mixing of reinforcements and reducing reinforcement agglomeration.
Dynamic Urban Transit Optimization: A Graph Neural Network Approach for Real-...IRJET Journal
This document discusses research on using graph neural networks (GNNs) for dynamic optimization of public transportation networks in real-time. GNNs represent transit networks as graphs with nodes as stops and edges as connections. The GNN model aims to optimize networks using real-time data on vehicle locations, arrival times, and passenger loads. This helps increase mobility, decrease traffic, and improve efficiency. The system continuously trains and infers to adapt to changing transit conditions, providing decision support tools. While research has focused on performance, more work is needed on security, socio-economic impacts, contextual generalization of models, continuous learning approaches, and effective real-time visualization.
Structural Analysis and Design of Multi-Storey Symmetric and Asymmetric Shape...IRJET Journal
This document summarizes a research project that aims to compare the structural performance of conventional slab and grid slab systems in multi-story buildings using ETABS software. The study will analyze both symmetric and asymmetric building models under various loading conditions. Parameters like deflections, moments, shears, and stresses will be examined to evaluate the structural effectiveness of each slab type. The results will provide insights into the comparative behavior of conventional and grid slabs to help engineers and architects select appropriate slab systems based on building layouts and design requirements.
A Review of “Seismic Response of RC Structures Having Plan and Vertical Irreg...IRJET Journal
This document summarizes and reviews a research paper on the seismic response of reinforced concrete (RC) structures with plan and vertical irregularities, with and without infill walls. It discusses how infill walls can improve or reduce the seismic performance of RC buildings, depending on factors like wall layout, height distribution, connection to the frame, and relative stiffness of walls and frames. The reviewed research paper analyzes the behavior of infill walls, effects of vertical irregularities, and seismic performance of high-rise structures under linear static and dynamic analysis. It studies response characteristics like story drift, deflection and shear. The document also provides literature on similar research investigating the effects of infill walls, soft stories, plan irregularities, and different
This document provides a review of machine learning techniques used in Advanced Driver Assistance Systems (ADAS). It begins with an abstract that summarizes key applications of machine learning in ADAS, including object detection, recognition, and decision-making. The introduction discusses the integration of machine learning in ADAS and how it is transforming vehicle safety. The literature review then examines several research papers on topics like lightweight deep learning models for object detection and lane detection models using image processing. It concludes by discussing challenges and opportunities in the field, such as improving algorithm robustness and adaptability.
Long Term Trend Analysis of Precipitation and Temperature for Asosa district,...IRJET Journal
The document analyzes temperature and precipitation trends in Asosa District, Benishangul Gumuz Region, Ethiopia from 1993 to 2022 based on data from the local meteorological station. The results show:
1) The average maximum and minimum annual temperatures have generally decreased over time, with maximum temperatures decreasing by a factor of -0.0341 and minimum by -0.0152.
2) Mann-Kendall tests found the decreasing temperature trends to be statistically significant for annual maximum temperatures but not for annual minimum temperatures.
3) Annual precipitation in Asosa District showed a statistically significant increasing trend.
The conclusions recommend development planners account for rising summer precipitation and declining temperatures in
P.E.B. Framed Structure Design and Analysis Using STAAD ProIRJET Journal
This document discusses the design and analysis of pre-engineered building (PEB) framed structures using STAAD Pro software. It provides an overview of PEBs, including that they are designed off-site with building trusses and beams produced in a factory. STAAD Pro is identified as a key tool for modeling, analyzing, and designing PEBs to ensure their performance and safety under various load scenarios. The document outlines modeling structural parts in STAAD Pro, evaluating structural reactions, assigning loads, and following international design codes and standards. In summary, STAAD Pro is used to design and analyze PEB framed structures to ensure safety and code compliance.
A Review on Innovative Fiber Integration for Enhanced Reinforcement of Concre...IRJET Journal
This document provides a review of research on innovative fiber integration methods for reinforcing concrete structures. It discusses studies that have explored using carbon fiber reinforced polymer (CFRP) composites with recycled plastic aggregates to develop more sustainable strengthening techniques. It also examines using ultra-high performance fiber reinforced concrete to improve shear strength in beams. Additional topics covered include the dynamic responses of FRP-strengthened beams under static and impact loads, and the performance of preloaded CFRP-strengthened fiber reinforced concrete beams. The review highlights the potential of fiber composites to enable more sustainable and resilient construction practices.
Survey Paper on Cloud-Based Secured Healthcare SystemIRJET Journal
This document summarizes a survey on securing patient healthcare data in cloud-based systems. It discusses using technologies like facial recognition, smart cards, and cloud computing combined with strong encryption to securely store patient data. The survey found that healthcare professionals believe digitizing patient records and storing them in a centralized cloud system would improve access during emergencies and enable more efficient care compared to paper-based systems. However, ensuring privacy and security of patient data is paramount as healthcare incorporates these digital technologies.
Review on studies and research on widening of existing concrete bridgesIRJET Journal
This document summarizes several studies that have been conducted on widening existing concrete bridges. It describes a study from China that examined load distribution factors for a bridge widened with composite steel-concrete girders. It also outlines challenges and solutions for widening a bridge in the UAE, including replacing bearings and stitching the new and existing structures. Additionally, it discusses two bridge widening projects in New Zealand that involved adding precast beams and stitching to connect structures. Finally, safety measures and challenges for strengthening a historic bridge in Switzerland under live traffic are presented.
React based fullstack edtech web applicationIRJET Journal
The document describes the architecture of an educational technology web application built using the MERN stack. It discusses the frontend developed with ReactJS, backend with NodeJS and ExpressJS, and MongoDB database. The frontend provides dynamic user interfaces, while the backend offers APIs for authentication, course management, and other functions. MongoDB enables flexible data storage. The architecture aims to provide a scalable, responsive platform for online learning.
A Comprehensive Review of Integrating IoT and Blockchain Technologies in the ...IRJET Journal
This paper proposes integrating Internet of Things (IoT) and blockchain technologies to help implement objectives of India's National Education Policy (NEP) in the education sector. The paper discusses how blockchain could be used for secure student data management, credential verification, and decentralized learning platforms. IoT devices could create smart classrooms, automate attendance tracking, and enable real-time monitoring. Blockchain would ensure integrity of exam processes and resource allocation, while smart contracts automate agreements. The paper argues this integration has potential to revolutionize education by making it more secure, transparent and efficient, in alignment with NEP goals. However, challenges like infrastructure needs, data privacy, and collaborative efforts are also discussed.
A REVIEW ON THE PERFORMANCE OF COCONUT FIBRE REINFORCED CONCRETE.IRJET Journal
This document provides a review of research on the performance of coconut fibre reinforced concrete. It summarizes several studies that tested different volume fractions and lengths of coconut fibres in concrete mixtures with varying compressive strengths. The studies found that coconut fibre improved properties like tensile strength, toughness, crack resistance, and spalling resistance compared to plain concrete. Volume fractions of 2-5% and fibre lengths of 20-50mm produced the best results. The document concludes that using a 4-5% volume fraction of coconut fibres 30-40mm in length with M30-M60 grade concrete would provide benefits based on previous research.
Optimizing Business Management Process Workflows: The Dynamic Influence of Mi...IRJET Journal
The document discusses optimizing business management processes through automation using Microsoft Power Automate and artificial intelligence. It provides an overview of Power Automate's key components and features for automating workflows across various apps and services. The document then presents several scenarios applying automation solutions to common business processes like data entry, monitoring, HR, finance, customer support, and more. It estimates the potential time and cost savings from implementing automation for each scenario. Finally, the conclusion emphasizes the transformative impact of AI and automation tools on business processes and the need for ongoing optimization.
Multistoried and Multi Bay Steel Building Frame by using Seismic DesignIRJET Journal
The document describes the seismic design of a G+5 steel building frame located in Roorkee, India according to Indian codes IS 1893-2002 and IS 800. The frame was analyzed using the equivalent static load method and response spectrum method, and its response in terms of displacements and shear forces were compared. Based on the analysis, the frame was designed as a seismic-resistant steel structure according to IS 800:2007. The software STAAD Pro was used for the analysis and design.
Cost Optimization of Construction Using Plastic Waste as a Sustainable Constr...IRJET Journal
This research paper explores using plastic waste as a sustainable and cost-effective construction material. The study focuses on manufacturing pavers and bricks using recycled plastic and partially replacing concrete with plastic alternatives. Initial results found that pavers and bricks made from recycled plastic demonstrate comparable strength and durability to traditional materials while providing environmental and cost benefits. Additionally, preliminary research indicates incorporating plastic waste as a partial concrete replacement significantly reduces construction costs without compromising structural integrity. The outcomes suggest adopting plastic waste in construction can address plastic pollution while optimizing costs, promoting more sustainable building practices.
DEEP LEARNING FOR SMART GRID INTRUSION DETECTION: A HYBRID CNN-LSTM-BASED MODELgerogepatton
As digital technology becomes more deeply embedded in power systems, protecting the communication
networks of Smart Grids (SG) has emerged as a critical concern. Distributed Network Protocol 3 (DNP3)
represents a multi-tiered application layer protocol extensively utilized in Supervisory Control and Data
Acquisition (SCADA)-based smart grids to facilitate real-time data gathering and control functionalities.
Robust Intrusion Detection Systems (IDS) are necessary for early threat detection and mitigation because
of the interconnection of these networks, which makes them vulnerable to a variety of cyberattacks. To
solve this issue, this paper develops a hybrid Deep Learning (DL) model specifically designed for intrusion
detection in smart grids. The proposed approach is a combination of the Convolutional Neural Network
(CNN) and the Long-Short-Term Memory algorithms (LSTM). We employed a recent intrusion detection
dataset (DNP3), which focuses on unauthorized commands and Denial of Service (DoS) cyberattacks, to
train and test our model. The results of our experiments show that our CNN-LSTM method is much better
at finding smart grid intrusions than other deep learning algorithms used for classification. In addition,
our proposed approach improves accuracy, precision, recall, and F1 score, achieving a high detection
accuracy rate of 99.50%.
6th International Conference on Machine Learning & Applications (CMLA 2024)ClaraZara1
6th International Conference on Machine Learning & Applications (CMLA 2024) will provide an excellent international forum for sharing knowledge and results in theory, methodology and applications of on Machine Learning & Applications.
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
Advanced control scheme of doubly fed induction generator for wind turbine us...IJECEIAES
This paper describes a speed control device for generating electrical energy on an electricity network based on the doubly fed induction generator (DFIG) used for wind power conversion systems. At first, a double-fed induction generator model was constructed. A control law is formulated to govern the flow of energy between the stator of a DFIG and the energy network using three types of controllers: proportional integral (PI), sliding mode controller (SMC) and second order sliding mode controller (SOSMC). Their different results in terms of power reference tracking, reaction to unexpected speed fluctuations, sensitivity to perturbations, and resilience against machine parameter alterations are compared. MATLAB/Simulink was used to conduct the simulations for the preceding study. Multiple simulations have shown very satisfying results, and the investigations demonstrate the efficacy and power-enhancing capabilities of the suggested control system.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024