This document summarizes research on characterizing titanium dioxide to improve the photon-to-current efficiency in dye-sensitized solar cells. The researchers studied processes like sintering the porous titanium dioxide layer and dye soaking. They observed an increase in efficiency by tuning the dye coverage of the porous titanium dioxide, which enhanced light absorption and decreased surface traps. Kinetic studies of dye adsorption were conducted using UV-Vis spectroscopy to fit absorption curves to pseudosecond-order chemical adsorption processes. The characterization techniques improved understanding and further developments of dye-sensitized solar cells.
Plasmonics can enable more efficient photovoltaic (PV) solar cells by improving light absorption. Key advantages include:
1) Enabling the use of thin-film materials with short exciton diffusion lengths and more defects.
2) Reducing dark current to increase photocurrent and open-circuit voltage, raising efficiency.
3) Potentially decreasing costs by allowing 10-100x thinner active material layers through plasmonic light trapping effects.
Matter, Inc. describes a plasmonic technology that can substantially improve the efficiency of thin film solar cells. Simulation results show the technology is capable of increasing short circuit current by almost 50% through enhanced light trapping. The plasmonic structures are robust, scalable to deposit, and enable simultaneous light concentration and charge extraction. An ongoing development cycle aims to optimize coatings and fabricate prototype thin film cells to validate the performance enhancements predicted by simulations.
This document discusses the use of carbon nanotubes in solar panels to improve efficiency. It provides background on solar panels and carbon nanotubes, explaining their properties. It then details the history of carbon nanotube solar panels, how they are constructed, and how double-walled carbon nanotubes can be used as both light absorbers and charge carriers. Using carbon nanotubes allows solar panels to utilize infrared light and increase efficiency to potentially 80%. Their properties like high mobility and strength make them suitable for more efficient solar energy conversion.
- Carbon nanotubes are being used in solar panel technology to improve efficiency by allowing the panels to utilize infrared radiation. The nanotubes act as photoconversion sites and help transport charge carriers. This can increase theoretical efficiency to 80%.
- Double-walled carbon nanotubes are directly incorporated into thin film solar cells, creating a p-n heterojunction with silicon. Nanotubes serve as both a light absorber and charge transport layer. Initial tests show an efficiency over 1%.
- Advantages of carbon nanotube solar panels include improved efficiency, ability to operate at night, increased output voltage, and reduced material needs. However, the technology remains in the experimental stage.
This document provides an introduction to carbon nanotubes, including their potential applications. It discusses how carbon nanotubes can be used structurally in combat jackets, bridges, and for a proposed space elevator due to their high tensile strength. Electromagnetically, carbon nanotubes show promise for use in artificial muscles, displays, transistors, and conductive films. They may also help filter water and air more efficiently than current methods, and store hydrogen for fuel cells. The document outlines how carbon nanotubes could replace conventional computer memory and be used in golf balls and bicycles to enhance performance.
Plasmonics can enable more efficient photovoltaic (PV) solar cells by improving light absorption. Key advantages include:
1) Enabling the use of thin-film materials with short exciton diffusion lengths and more defects.
2) Reducing dark current to increase photocurrent and open-circuit voltage, raising efficiency.
3) Potentially decreasing costs by allowing 10-100x thinner active material layers through plasmonic light trapping effects.
Matter, Inc. describes a plasmonic technology that can substantially improve the efficiency of thin film solar cells. Simulation results show the technology is capable of increasing short circuit current by almost 50% through enhanced light trapping. The plasmonic structures are robust, scalable to deposit, and enable simultaneous light concentration and charge extraction. An ongoing development cycle aims to optimize coatings and fabricate prototype thin film cells to validate the performance enhancements predicted by simulations.
This document discusses the use of carbon nanotubes in solar panels to improve efficiency. It provides background on solar panels and carbon nanotubes, explaining their properties. It then details the history of carbon nanotube solar panels, how they are constructed, and how double-walled carbon nanotubes can be used as both light absorbers and charge carriers. Using carbon nanotubes allows solar panels to utilize infrared light and increase efficiency to potentially 80%. Their properties like high mobility and strength make them suitable for more efficient solar energy conversion.
- Carbon nanotubes are being used in solar panel technology to improve efficiency by allowing the panels to utilize infrared radiation. The nanotubes act as photoconversion sites and help transport charge carriers. This can increase theoretical efficiency to 80%.
- Double-walled carbon nanotubes are directly incorporated into thin film solar cells, creating a p-n heterojunction with silicon. Nanotubes serve as both a light absorber and charge transport layer. Initial tests show an efficiency over 1%.
- Advantages of carbon nanotube solar panels include improved efficiency, ability to operate at night, increased output voltage, and reduced material needs. However, the technology remains in the experimental stage.
This document provides an introduction to carbon nanotubes, including their potential applications. It discusses how carbon nanotubes can be used structurally in combat jackets, bridges, and for a proposed space elevator due to their high tensile strength. Electromagnetically, carbon nanotubes show promise for use in artificial muscles, displays, transistors, and conductive films. They may also help filter water and air more efficiently than current methods, and store hydrogen for fuel cells. The document outlines how carbon nanotubes could replace conventional computer memory and be used in golf balls and bicycles to enhance performance.
Nano technology involves manipulating materials at the nanoscale, or one billionth of a meter. An all-optical router using nano technology could route information carried by photons at near the speed of light without converting it to electricity first. Photonic crystals designed at the nanoscale could direct photons of specific wavelengths along pathways to route information optically. Manipulating photons using nanostructured materials could allow building optical devices like routers and repeaters to improve information transmission speeds and capabilities in telecommunications networks.
Silberberg Chemistry Molecular Nature Of Matter And Change 4e Copy2jeksespina
There are three main types of radioactive decay: alpha, beta, and gamma. Alpha decay involves emitting an alpha particle (helium nucleus) which decreases the mass and atomic numbers by 4 and 2 respectively. Beta decay involves emitting an electron or positron, which does not change mass number but increases or decreases the atomic number by 1. Gamma decay involves emitting high-energy photons without changing the nucleus. Nuclear equations must balance the total numbers of protons and nucleons between reactants and products.
This document summarizes a seminar presentation on carbon nanotube based solar cells. It begins with an introduction to carbon nanotubes, describing their cylindrical nanostructure formed from graphene sheets rolled at specific angles. It then discusses properties of carbon nanotubes that make them suitable for solar cells, such as their electrical conductivity. The document reviews different generations of solar cell technology and their limitations before describing how carbon nanotubes can be incorporated into dye-sensitized solar cells as transparent electrodes, replacing conventional materials like ITO. It presents results showing a carbon nanotube-based solar cell achieved 7.04% efficiency compared to 7.34% for a standard platinum electrode cell. In conclusion, carbon nanotube electrodes
Quantum dots are semiconductor nanocrystals that can emit light of varying wavelengths depending on their size. They have applications in display technology where they can convert blue light into red or green light. There are different types of quantum dot display systems including photo-enhanced, photo-emissive, and electro-emissive systems. Quantum dots offer benefits like high brightness, energy efficiency, and pure color emission.
Perovskite solar cells have increased in efficiency from below 5% in 2009 to over 20% in 2014, making them a promising solar cell technology. Researchers have discovered ways to improve perovskite solar cells using liquid inks, upconversion and downconversion techniques, light-absorbing dyes, quantum dots, organic and polymer materials, and adaptive and nanostructured surfaces. These techniques aim to lower the cost and increase the efficiency of solar cells.
Nano based technology for renewable energy generationjoyak
The document discusses the use of nanotechnology for renewable energy generation. It describes how dye-sensitized solar cells use nanostructures to absorb sunlight more efficiently and cheaply than traditional silicon-based solar cells. The document also discusses how solar cells work by absorbing photons that excite electrons, generating electricity, and how not all absorbed light is converted. Finally, it provides an overview of natural energy sources like hydrocarbons and their effects compared to more sustainable renewable sources like solar, wind, and biomass that are being advanced through nanotechnology approaches.
Carbon Nanotubes Properties and its ApplicationsArun Kumar
This document discusses carbon nanotubes. It defines a carbon nanotube as a tube-shaped material made of carbon that has a diameter on the nanometer scale, which is about 10,000 times smaller than a human hair. Carbon nanotubes are categorized as either single-walled or multi-walled. The document lists several applications of carbon nanotubes, including in thermal conductivity, energy storage, structural materials, fibers, biomedicine, filtration, electronics, and bioengineering. Several synthesis methods for carbon nanotubes are also described, such as arc discharge, laser ablation, chemical vapor deposition, and ball milling.
Carbon nanotubes have extraordinary strength and unique electrical properties. They are classified as single-walled or multi-walled nanotubes. Common synthesis methods are arc discharge, laser ablation, and chemical vapor deposition. Key milestones include the discovery of 18.5 cm long nanotubes and the thinnest freestanding single-walled nanotube of about 4.3 Angstroms in diameter. Carbon nanotubes have immense strength, are harder than diamond, and are excellent thermal and electrical conductors.
Guided nanophotonic devices and applications - Christiano de MatosCPqD
MackGraphe is a new research center at Mackenzie Presbyterian University dedicated to investigating the properties of graphene and other nanomaterials with an applied engineering perspective. The center initiated activities in 2012 with a focus on graphene synthesis, characterization, and photonic device development. Previous work included functionalizing optical fiber tips with carbon nanotubes for mode-locked fiber lasers and depositing polymer films inside hollow-core photonic crystal fibers. Current research interests include exploiting graphene's saturable absorption, nonlinearity, and plasmonic properties for all-integrated photonic devices based on nonlinear and plasmonic effects.
Study on momentum density in magnetic semiconductor MnTe by positron annihila...IJASCSE
This 3-sentence summary provides the key information from the document:
The document presents a study on calculating momentum density in the magnetic semiconductor MnTe using positron annihilation. Pseudopotential band structure calculations were used to derive electron and positron wave functions in the independent particle model. Electron-positron momentum densities were then calculated for specific planes in MnTe and the results were used to analyze positron effects in the material.
The document summarizes optical properties of nanomaterials. It discusses topics like optics, optical properties of materials, thin film interference, luminescence, photonic crystals, photoconductivity, solar cells, and optical properties of quantum wells and quantum dots. In particular, it explains how the size-dependent band gap of quantum dots leads to size-tunable fluorescence colors, making quantum dots useful for applications like biological imaging and white LEDs.
The document summarizes a presentation on numerical modeling of photonic nanostructures and organic solar cells. It introduces photonic crystals, quasi-crystals, and random nanostructures. It then discusses using the finite-difference time-domain method to model the photonic properties of quasi-random nanostructures. Finally, it examines using nanostructures to trap light and increase absorption in organic solar cells through simulation and modeling exciton diffusion.
Lattice Energy LLC-Nickel-seed LENR Networks-April 20 2011Lewis Larsen
The document discusses Low Energy Nuclear Reactions (LENRs) and the Widom-Larsen theory of LENRs.
The Widom-Larsen theory proposes that: 1) electromagnetic radiation increases the mass of surface plasmon electrons on a metallic hydride surface, 2) these heavy electrons interact via the weak force with surface protons/deuterons to produce ultra low momentum neutrons, 3) these neutrons are captured by nearby nuclei, producing heavier isotopes that may decay via beta decay. This process could potentially produce excess heat through various nuclear reactions and decays. The theory aims to explain experimental observations of transmutation products and heat in LENR systems.
Nanowires are microscopic wires that have widths measured in nanometers, ranging from 40-50 nanometers. They have potential applications in electronics, energy storage, sensing and optoelectronics due to their unique properties. Specifically, semiconductor nanowires and carbon nanotubes have shown promise as building blocks for future nanoscale devices and circuits due to their ability to efficiently transport electrical carriers and exhibit critical device functions. However, carbon nanotubes have faced challenges in controlling their semiconducting or metallic properties and manipulating individual tubes, while nanowires allow for more rational and predictable assembly through control of their synthesis.
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.
This document provides an introduction to metamaterials and discusses their history and applications. It describes how metamaterials get their properties from their structure rather than their composition, allowing properties like a negative index of refraction. Early works are cited that proposed ring resonators could respond to light's magnetic field. The first experimental demonstration of a negative index material is summarized. Applications like electromagnetic cloaking are introduced, with some examples of cloaking other wave phenomena like sound and water waves. Research areas at BU like terahertz metamaterials and mechanically reconfigurable metamaterials are briefly outlined. In summary, the document traces the development of metamaterials from early theoretical proposals to demonstrations of exotic properties and applications.
Analysis Of Carbon Nanotubes And Quantum Dots In A Photovoltaic DeviceM. Faisal Halim
Analysis of Carbon Nanotubes and Quantum Dots in a Photovoltaic Device
A poster prepared by Francis and me; presented by Francis. I modified on of the photographs used, in this copy.
The document provides an overview of Objective-C, including:
- A brief history of Objective-C and its use by Apple and NeXT.
- Objective-C adds object-oriented messaging to C, allowing for object-oriented programming while still supporting C code.
- Key differences between Objective-C and C++ include Objective-C's focus on dynamic typing and runtime features over C++'s compile-time features.
Reaching Your Students Through Bloggingmmichalakos
The document is a presentation by Maria Michalakos, a 2nd grade teacher, about using blogging to engage students. It discusses the benefits of classroom blogging, including motivating students and providing opportunities for collaboration. It provides examples of successes, such as students becoming independent bloggers. The presentation provides tips for starting a blog, such as choosing a kid-friendly theme and making regular posts of student work. It also covers potential challenges and getting parents involved.
Në Token e Bekueme Shqipni, Atdheun e Gjergj Kastriotit – Skenderbeut, n’ Atë shkamb kuShqipja Dykrenare me kthetrat e veta ka shkrue Epopenë ma të lavdishme të qendresës sashekullore të Atdhetarizmit Shqiptar ...
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
Nano technology involves manipulating materials at the nanoscale, or one billionth of a meter. An all-optical router using nano technology could route information carried by photons at near the speed of light without converting it to electricity first. Photonic crystals designed at the nanoscale could direct photons of specific wavelengths along pathways to route information optically. Manipulating photons using nanostructured materials could allow building optical devices like routers and repeaters to improve information transmission speeds and capabilities in telecommunications networks.
Silberberg Chemistry Molecular Nature Of Matter And Change 4e Copy2jeksespina
There are three main types of radioactive decay: alpha, beta, and gamma. Alpha decay involves emitting an alpha particle (helium nucleus) which decreases the mass and atomic numbers by 4 and 2 respectively. Beta decay involves emitting an electron or positron, which does not change mass number but increases or decreases the atomic number by 1. Gamma decay involves emitting high-energy photons without changing the nucleus. Nuclear equations must balance the total numbers of protons and nucleons between reactants and products.
This document summarizes a seminar presentation on carbon nanotube based solar cells. It begins with an introduction to carbon nanotubes, describing their cylindrical nanostructure formed from graphene sheets rolled at specific angles. It then discusses properties of carbon nanotubes that make them suitable for solar cells, such as their electrical conductivity. The document reviews different generations of solar cell technology and their limitations before describing how carbon nanotubes can be incorporated into dye-sensitized solar cells as transparent electrodes, replacing conventional materials like ITO. It presents results showing a carbon nanotube-based solar cell achieved 7.04% efficiency compared to 7.34% for a standard platinum electrode cell. In conclusion, carbon nanotube electrodes
Quantum dots are semiconductor nanocrystals that can emit light of varying wavelengths depending on their size. They have applications in display technology where they can convert blue light into red or green light. There are different types of quantum dot display systems including photo-enhanced, photo-emissive, and electro-emissive systems. Quantum dots offer benefits like high brightness, energy efficiency, and pure color emission.
Perovskite solar cells have increased in efficiency from below 5% in 2009 to over 20% in 2014, making them a promising solar cell technology. Researchers have discovered ways to improve perovskite solar cells using liquid inks, upconversion and downconversion techniques, light-absorbing dyes, quantum dots, organic and polymer materials, and adaptive and nanostructured surfaces. These techniques aim to lower the cost and increase the efficiency of solar cells.
Nano based technology for renewable energy generationjoyak
The document discusses the use of nanotechnology for renewable energy generation. It describes how dye-sensitized solar cells use nanostructures to absorb sunlight more efficiently and cheaply than traditional silicon-based solar cells. The document also discusses how solar cells work by absorbing photons that excite electrons, generating electricity, and how not all absorbed light is converted. Finally, it provides an overview of natural energy sources like hydrocarbons and their effects compared to more sustainable renewable sources like solar, wind, and biomass that are being advanced through nanotechnology approaches.
Carbon Nanotubes Properties and its ApplicationsArun Kumar
This document discusses carbon nanotubes. It defines a carbon nanotube as a tube-shaped material made of carbon that has a diameter on the nanometer scale, which is about 10,000 times smaller than a human hair. Carbon nanotubes are categorized as either single-walled or multi-walled. The document lists several applications of carbon nanotubes, including in thermal conductivity, energy storage, structural materials, fibers, biomedicine, filtration, electronics, and bioengineering. Several synthesis methods for carbon nanotubes are also described, such as arc discharge, laser ablation, chemical vapor deposition, and ball milling.
Carbon nanotubes have extraordinary strength and unique electrical properties. They are classified as single-walled or multi-walled nanotubes. Common synthesis methods are arc discharge, laser ablation, and chemical vapor deposition. Key milestones include the discovery of 18.5 cm long nanotubes and the thinnest freestanding single-walled nanotube of about 4.3 Angstroms in diameter. Carbon nanotubes have immense strength, are harder than diamond, and are excellent thermal and electrical conductors.
Guided nanophotonic devices and applications - Christiano de MatosCPqD
MackGraphe is a new research center at Mackenzie Presbyterian University dedicated to investigating the properties of graphene and other nanomaterials with an applied engineering perspective. The center initiated activities in 2012 with a focus on graphene synthesis, characterization, and photonic device development. Previous work included functionalizing optical fiber tips with carbon nanotubes for mode-locked fiber lasers and depositing polymer films inside hollow-core photonic crystal fibers. Current research interests include exploiting graphene's saturable absorption, nonlinearity, and plasmonic properties for all-integrated photonic devices based on nonlinear and plasmonic effects.
Study on momentum density in magnetic semiconductor MnTe by positron annihila...IJASCSE
This 3-sentence summary provides the key information from the document:
The document presents a study on calculating momentum density in the magnetic semiconductor MnTe using positron annihilation. Pseudopotential band structure calculations were used to derive electron and positron wave functions in the independent particle model. Electron-positron momentum densities were then calculated for specific planes in MnTe and the results were used to analyze positron effects in the material.
The document summarizes optical properties of nanomaterials. It discusses topics like optics, optical properties of materials, thin film interference, luminescence, photonic crystals, photoconductivity, solar cells, and optical properties of quantum wells and quantum dots. In particular, it explains how the size-dependent band gap of quantum dots leads to size-tunable fluorescence colors, making quantum dots useful for applications like biological imaging and white LEDs.
The document summarizes a presentation on numerical modeling of photonic nanostructures and organic solar cells. It introduces photonic crystals, quasi-crystals, and random nanostructures. It then discusses using the finite-difference time-domain method to model the photonic properties of quasi-random nanostructures. Finally, it examines using nanostructures to trap light and increase absorption in organic solar cells through simulation and modeling exciton diffusion.
Lattice Energy LLC-Nickel-seed LENR Networks-April 20 2011Lewis Larsen
The document discusses Low Energy Nuclear Reactions (LENRs) and the Widom-Larsen theory of LENRs.
The Widom-Larsen theory proposes that: 1) electromagnetic radiation increases the mass of surface plasmon electrons on a metallic hydride surface, 2) these heavy electrons interact via the weak force with surface protons/deuterons to produce ultra low momentum neutrons, 3) these neutrons are captured by nearby nuclei, producing heavier isotopes that may decay via beta decay. This process could potentially produce excess heat through various nuclear reactions and decays. The theory aims to explain experimental observations of transmutation products and heat in LENR systems.
Nanowires are microscopic wires that have widths measured in nanometers, ranging from 40-50 nanometers. They have potential applications in electronics, energy storage, sensing and optoelectronics due to their unique properties. Specifically, semiconductor nanowires and carbon nanotubes have shown promise as building blocks for future nanoscale devices and circuits due to their ability to efficiently transport electrical carriers and exhibit critical device functions. However, carbon nanotubes have faced challenges in controlling their semiconducting or metallic properties and manipulating individual tubes, while nanowires allow for more rational and predictable assembly through control of their synthesis.
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.
This document provides an introduction to metamaterials and discusses their history and applications. It describes how metamaterials get their properties from their structure rather than their composition, allowing properties like a negative index of refraction. Early works are cited that proposed ring resonators could respond to light's magnetic field. The first experimental demonstration of a negative index material is summarized. Applications like electromagnetic cloaking are introduced, with some examples of cloaking other wave phenomena like sound and water waves. Research areas at BU like terahertz metamaterials and mechanically reconfigurable metamaterials are briefly outlined. In summary, the document traces the development of metamaterials from early theoretical proposals to demonstrations of exotic properties and applications.
Analysis Of Carbon Nanotubes And Quantum Dots In A Photovoltaic DeviceM. Faisal Halim
Analysis of Carbon Nanotubes and Quantum Dots in a Photovoltaic Device
A poster prepared by Francis and me; presented by Francis. I modified on of the photographs used, in this copy.
The document provides an overview of Objective-C, including:
- A brief history of Objective-C and its use by Apple and NeXT.
- Objective-C adds object-oriented messaging to C, allowing for object-oriented programming while still supporting C code.
- Key differences between Objective-C and C++ include Objective-C's focus on dynamic typing and runtime features over C++'s compile-time features.
Reaching Your Students Through Bloggingmmichalakos
The document is a presentation by Maria Michalakos, a 2nd grade teacher, about using blogging to engage students. It discusses the benefits of classroom blogging, including motivating students and providing opportunities for collaboration. It provides examples of successes, such as students becoming independent bloggers. The presentation provides tips for starting a blog, such as choosing a kid-friendly theme and making regular posts of student work. It also covers potential challenges and getting parents involved.
Në Token e Bekueme Shqipni, Atdheun e Gjergj Kastriotit – Skenderbeut, n’ Atë shkamb kuShqipja Dykrenare me kthetrat e veta ka shkrue Epopenë ma të lavdishme të qendresës sashekullore të Atdhetarizmit Shqiptar ...
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
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.
This document provides an overview and comparison of three types of solar cells: crystalline silicon solar cells, plasmonic solar cells, and dye-sensitized solar cells. Plasmonic solar cells use metal nanoparticles to increase light absorption and scattering in thin-film solar cells. Dye-sensitized solar cells separate the functions of light absorption and charge transport to provide a potentially low-cost alternative to traditional p-n junction photovoltaics. The document discusses the operating principles, advantages, and design considerations of plasmonic and dye-sensitized solar cells, with a brief overview of conventional crystalline silicon photovoltaics provided for context.
Comparison of Different types of Solar Cells – a Reviewiosrjce
IOSR Journal of Electrical and Electronics Engineering(IOSR-JEEE) is a double blind peer reviewed International Journal that provides rapid publication (within a month) of articles in all areas of electrical and electronics engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electrical and electronics engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
Combined X-ray diffraction and X-ray fluorescence allows researchers to optimize the performance of
multi-layered, post-fabricated organic photovoltaic devices doped with gold nanoparticles.
This document discusses the use of photoluminescence to analyze optimal growth factors in quantum nanowires for solar energy applications. It describes how nanowire semiconductors present a more economical alternative to planar semiconductors for solar cells. The study aims to observe the photoluminescence of different gallium arsenide quantum wire samples grown using molecular beam epitaxy under various conditions to determine the most efficient samples. Molecular beam epitaxy is described as the bottom-up technique used to grow the nanowire semiconductor samples by depositing elemental beams of gallium and arsenide onto a silicon wafer substrate.
Nanoparticles range from 1-100nm in size and may exhibit size-dependent properties different from bulk materials. Mesoporous silica nanoparticles have been created with diameters of 20nm, 45nm, and 80nm using TEM and SEM imaging. Quantum dots are semiconductor nanoparticles less than 10nm that show quantized energy levels resulting in size-dependent colors from their light emission. Potential applications of nanoparticles and quantum dots include biomedical imaging, solar cells, LEDs and other electronic and optical devices.
The document summarizes research into using plasmonic silver nanowires to harvest hot electrons for chemical reactions. Nanowires were synthesized inside anodic aluminum oxide nanopores using electrodeposition. Scanning electron microscopy images showed the nanowires had a unique stacked ring structure, and absorption spectroscopy indicated absorption in the visible spectrum. Removing the alumina template left just the silver nanowire structures. Future work will refine the nanostructures and integrate them into a device for energy storage 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 provides an overview of dye sensitized solar cells (DSSC). It discusses the principle and working of DSSCs, including the key components - a photosensitive dye, nanostructured semiconductor (typically TiO2), redox electrolyte, and two electrodes. Upon light absorption, electrons are injected from the dye into the semiconductor. The electrolyte regenerates the oxidized dye and transports electrons between the electrodes. The document outlines the preparation, applications, and commercial potential of DSSCs, noting their advantages over silicon solar cells.
This presentation dives into the deep realms of nano-chemistry starting from the very basics to a sufficient advanced level. Nano-chemistry has always been a very intriguing topic for most of us as we see it in movies more than frequently. If not, we at least hear some explanation about a curious event that relates directly to nano-chemistry.
Diving into the depths of those explanations related to nano-chemistry and revealing the actual facts about nano-chemistry and its related topics. We have formulated this presentation to become a crucial source of information regarding nano-chemistry and its other related terms.
It is also a study material for Basics of Chemistry subject taught during the 1st or 2nd semesters during B.E. / B.Tech degree courses.
In this article, we are introducing some technique of growth Nanowire for Nanostructures for physics, A Nanowire considered as a Nanostructure which is build blocks for the generation of electrons protons neutrons positions and the sensor and also the energy applications. In this project, we are to synthesis and growth of semiconductor nanowire made by metallic both of the axial and radial structure and their properties discuss here. In one-dimensional nanostructure of control, density States turned into the electronic and optic properties. There is a new technique of growth metallic and semiconducting material develop in the International Science. A nanowire is a nanostructure, with the diameter of the order of a nanometer (10−9 meters) and an unconstrained length. At these scales, quantum mechanical effects are important — which coined the term "quantum wires.” Quantum confinement produces new material behaviour/phenomena. Based on the degree of confinement different Structures arise.
Synthesis, Characterization of ZnS nanoparticles by Coprecipitation method us...IOSR Journals
ZnS nanoparticles are prepared by coprecipitation method using various capping agents like PVP (polyvinylpyrrolidone), PVA (polyvinylalcohol) and PEG-4000 (polyethyleneglycol). These are characterized by UV-Visible spectra, X-ray diffraction (XRD) studies, Fourier Transform Infra-red spectra (FTIR) and Transmission electron microscopy (TEM). UV-Visible absorption spectra are used to find the optical band gap and the values obtained have been found to be in the range of 3.80-4.00eV. The particle size of nanoparticles calculated from XRD pattern has been in the range of 2-4 nm. It is also observed that the particle size of nanoparticle is affected by the nature of capping agent. Photo catalytic degradation of xylenol orange (XO) by the nanoparticles shows that these act as photo catalysts under sunlight irradiation. The XO dye was degraded more than 87.24, 83.42 and 73.05% in the presence of PEG-4000, PVA and PVP capped ZnS nanoparticles in 120, 150 and 180 min. respectively. The kinetics of catalyzed by synthesized ZnS nanoparticles with XO dye follows pseudo-first order kinetics with reasonable apparent rate constants.
Calculation of Optical Properties of Nano ParticlePHYSICS 5535- .docxRAHUL126667
Calculation of Optical Properties of Nano Particle
PHYSICS 5535- Optical Properties Matter-Spring 2017
Raznah Yami
Outline
1. Introduction: this part gives a precise overview of the whole paper. It begins by illustrating a brief introduction and importance of Nano Particles and the theoretical approaches used for their calculation.
2. Main idea: this section provides a step-by-step in-depth analysis of recently developed theories the calculation of optical properties of nanoparticles. It also provides calculation and equations employed these approaches.
2.1 Optical Properties of Nanoparticles: this section talks about the basics principles and governing the optical behavior of Nano particles and provides in-depth knowledge of different phenomena observed while dealing with optical properties of Nano particles.
2.2 Mie-Theory: the research provides exhaustive information the study optical properties of nanoparticles using Mie theory. This research focuses on Mie theory for the calculation of optical properties of Nano particle according to which we can calculate the place of surface Plasmon resonance in optical spectra of metallic spherical nanoparticle.
2.3 Discrete Dipole Approximation method: this section enumerates sufficient information about the calculation of absorption and scattering efficiencies and optical resonance wavelengths for three commonly used classes of nanoparticles: gold Nano spheres, silica-gold Nano shells, and gold Nano rods and we examine the magneto-optical scattering from nanometer-scale structures using a discrete dipole approximation.
3. Conclusion: This section provides a summary of the most important points, which presents an overview of the practical application and calculation methods of optical properties of Nano particles talking about core principles, which therefore explain the behavior exhibited by nanoparticles.
List of figures:
Figure 1: Localized surface Plasmon resonance ,resulting from the collective oscillations of delocalized electrons in response to an external electric field
Figure 2: Absorption spectra of semiconductor nanoparticles of different diameter. Right-nanoparticles suspended in solution.
Figure 3: Comparison of absorbance along increasing wavelength between Nano GaAs (7-15 nm) and Bulk GaAs showing an apparent blue shift
Figure 4: Showing the effect of blue shift because of quantum confinement as the wavelength shifts from 1100 nm to 2000 nm when we move from particle size of 9nm to parcile size of 3 nm.
Figure 5: Emission spectra of several sizes of (Cdse) Zns core-shell quantum dots.
Figure 6: The optical spectra and transmission electron micrographs for the particles in vials 1–5 are also shown. Scale bars in micrographs are all 100 nm
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Chapter wise All Notes of First year Basic Civil Engineering.pptxDenish Jangid
Chapter wise All Notes of First year Basic Civil Engineering
Syllabus
Chapter-1
Introduction to objective, scope and outcome the subject
Chapter 2
Introduction: Scope and Specialization of Civil Engineering, Role of civil Engineer in Society, Impact of infrastructural development on economy of country.
Chapter 3
Surveying: Object Principles & Types of Surveying; Site Plans, Plans & Maps; Scales & Unit of different Measurements.
Linear Measurements: Instruments used. Linear Measurement by Tape, Ranging out Survey Lines and overcoming Obstructions; Measurements on sloping ground; Tape corrections, conventional symbols. Angular Measurements: Instruments used; Introduction to Compass Surveying, Bearings and Longitude & Latitude of a Line, Introduction to total station.
Levelling: Instrument used Object of levelling, Methods of levelling in brief, and Contour maps.
Chapter 4
Buildings: Selection of site for Buildings, Layout of Building Plan, Types of buildings, Plinth area, carpet area, floor space index, Introduction to building byelaws, concept of sun light & ventilation. Components of Buildings & their functions, Basic concept of R.C.C., Introduction to types of foundation
Chapter 5
Transportation: Introduction to Transportation Engineering; Traffic and Road Safety: Types and Characteristics of Various Modes of Transportation; Various Road Traffic Signs, Causes of Accidents and Road Safety Measures.
Chapter 6
Environmental Engineering: Environmental Pollution, Environmental Acts and Regulations, Functional Concepts of Ecology, Basics of Species, Biodiversity, Ecosystem, Hydrological Cycle; Chemical Cycles: Carbon, Nitrogen & Phosphorus; Energy Flow in Ecosystems.
Water Pollution: Water Quality standards, Introduction to Treatment & Disposal of Waste Water. Reuse and Saving of Water, Rain Water Harvesting. Solid Waste Management: Classification of Solid Waste, Collection, Transportation and Disposal of Solid. Recycling of Solid Waste: Energy Recovery, Sanitary Landfill, On-Site Sanitation. Air & Noise Pollution: Primary and Secondary air pollutants, Harmful effects of Air Pollution, Control of Air Pollution. . Noise Pollution Harmful Effects of noise pollution, control of noise pollution, Global warming & Climate Change, Ozone depletion, Greenhouse effect
Text Books:
1. Palancharmy, Basic Civil Engineering, McGraw Hill publishers.
2. Satheesh Gopi, Basic Civil Engineering, Pearson Publishers.
3. Ketki Rangwala Dalal, Essentials of Civil Engineering, Charotar Publishing House.
4. BCP, Surveying volume 1
Chapter wise All Notes of First year Basic Civil Engineering.pptx
Chracterization of ti o2 towards higher of incident photon to-current efficiency in dss-cs
1. Physicalia (2008)3 pp.149-.j60
l,4as.30
CHARACTERIZATION TiO2TOWARDSHIGHER
OF
INCIDENTPHOTON-TO-CURRENT
EFFICIENCY DYE
IN
SENSITIZED
SOLARCELLS*
W. Moonsl,K. Vandewall,P. Robaeysl,G. Krishnal and J. Mancal'2
1lnstituutvoor
Materiaalonderzoek,
universiteitHasselt,
Wete nschapspark1, 3590Diepen eek.
b
z IMEC-IMOMEC
vzw, Wetenschapspark 3Sg0Diepenbeek
1,
Summaryof the work, awardedwith the prize ot the best poster presentation Wouter Moons at
by
the General
Scienfific
Meetingofthe BPS at the Universit6 Librede Bruxelles ly'av 200g
on 21,
Abstract
Worldenergyprovision probably
is one of the most challenging engagements the 2.1"t
of
century.
Amongihe novelgeneration solarcell concepts, so called"GrAEel ce " or
the
Dye Sensitized
SolarCell is likelyone of the most promising. is basedon the spectral
lt
sensitization a thin ceramic mesoporousmembraneby suitabletransitionmetal
of
complexes (=dye).
The film consists nanometer-sized
of colloidal
titaniumdioxideparticles
sinteredtogether allow for chargecarrierlransport. focusing the fundamenial,
to By on
thoughmostlyignored,
processes
like sintering
the anataseTiO, porouslayer and dye
soaking, incfeasein IPCE is observed.
an Duringthe brief heatingof the mdso-porous
film,calcination the TiO, particles
of takes place.This calcination monitored
is in-situby
electrical
measurements. tuningthe dye coverage porousTiO2,light absorption
By of is
enhanced,and suTfacetraps are decreased.In this work the adsorptionkjneticsof
ruthenium-based havebeenstudiedby measuring optical
dyes the absofbance spectraof
the sensitized
filmsusingUV-Vis
spectroscopy. resulting
The effective
aDsoroance
curyes
as functionof time were successfully
fltted as pseudosecond-order chemicalsorption
processes.Both presentedcharacterization techniquesresultedto be efficienttools
towards betterunderstanding further
a and improvements dye sensitized
of solarcells
149
2. lntroduction
effect by Becquerel[1]' researchers and
Ever since the discoveryof the photoelectric
sunlightcouldbe
engineers have been enthralled the idea that freelyavailable
with
captured converted electrical
and into power'
'thatgenerates photovoltage
a by
The mostcommonly known solarcells,i'€' a device
The semiconductor
shining lightuponit, incorporate pn-junction a semiconductor'
a in
solarspectrum' Dependent the
on
material to be ableto absorb largepartof the
has a
moreor lessclose
absorption properties the material lightis absorbed a region
ol the in
pairs are generated and if
to the surfiace. When photonsare absorbed'electronhole
their recombination prevented
is they can reachthe junctionwherethey are separated
absorbing semiconductors silicon
like mostcaniers
by an electric field.Evenfor weakly
are generated nearthe surface'The pn-junction whichseparates emitterand base
the
a high collection probability free
for
layer is very closeto the surfacein orderto have
carriers.. operating
The principtes beendescribed manypublications [3]'
have in [2]
Sofar,thescienceofso|arce||shasbeendominatedbydevicesinwhichthejuncti
betweeninorganicsolid-statemateria|s,usua|lydopedformsofcrySta||ineoram
silicon.lnrecentyears,novelclassesofphotovoltaicmaterialsystemshaveimer
solarcellscuFently become broader
of interest'
suchas, nano-crystalline organic
and
roughly molecular polymdr
into and organicsolarcellsor into
Thesecellscanbe divided
flallayer systems bulkheterojunctionsl4]'
and
cheapto fabricate(theexpensive
solarcells,whichare relatively
Thesethird generation
high-temperature high-vacuum
and processes neededfor the
and energy-intensive
on flexiblesubstrates'and can be
traditionaldevicescan be avoided),can be used
shapedortintedtosuitdomesticdevicesorarchitecturalordecorativeapp|icationsl5
developed molecular
a system solarlight
photovoltraic for
ln 1991GreEeland O'regan
of
basedon the speclralsensitization
harvesting Gonversion electricitylG] lt is
and to [4'
metalcomplexes' Jilmconsists
transition The of
a thin ceramicmembrane suitable
Dy
nanometer-sizedcol|oida|titaniumdioxideparticlessinteredtogethertoa||owforch
chromophore' thesemembranes give
Whenderivatized a suitable
transport'
carrier with
l
150
3. extraordinaryefficienciesfor the conversionof incident photons into electric current
(IPCE).These cells are referred as "Gratzel
to cells"or .Dye Sensitized Solar Cells"
(DSSC).
operation the Dye-Sensitized
Figure 1: Schematic of SolarCell
presentation the operation
A schematic of principle givenin Figure The heartof the
is 1.
oxidefilm (see
deviceis a mesoporous Figure typically
2), 10pmthick,whichis made
of tiny nano-crystals,
interconnected allow electronic
to conduction take place.Oxides
to
suchas TiOzZnO,SnOz suchas CdSe,are the preferred
and Nb2O5or chalcogenides
,
compounds[8]. till now, titanium
Up dioxidehas been the material choicefor these
of
applications. becauseof its large band gap (3_3.2eV), TiO, intrinsicly
Unfortunately,
part of the solar emissionand so has low conversion
absorbsonly the ultraviolet
efficiencies. solutionlies in the separation the opticalabsorption
The of and charge-
151
4. generating using an electron
functions, absorbing the visible
transfersensitizer' in
gap' Photo-
region injectchargecaniersintoa substrate a wideband
spectral to with
excitalionofthesensitizer(S)resu|tsintheinjectionofane|ectroninthecond
Theoriginalstateofthe dyeis subbequently restored eleclron
by donation
bandof TiOz.
from the eleclrolyte, impregnated the porous
in '-TiO2'usuallyan organicsolvent
containing redoxsystem, coupleis used'Thusresults a
suchas the iodide/triiodide in
three dimensional networkwith an enormouscontactarea betweenthe two types of
materials, wherecharge tansportis bestdescribed a random
by walkmodel[9]' The
intercepts recapture the conduction
the of band
regeneration the sensitizer iodide
of by
electron the oxidized
by dye.A dense TiOzlayer(seeFigure is sputtered a hole-
3) as
in
blocking layerto reducerecombination the electrode' iodideis regenerated
at The
typically withPlatinum'
coated
tum by the reduction triiodide the counter-electrode'
of at
migration through external
the load' The
The circuitis beingcompleted electron
via
generated underillumination conesponds the difference
to between Fermi
the
voltage
overallthe
levelof the electron the solidand the redoxpotential the electrolyte'
in of
devicegenerates electricpowerfrom lightwithoutsuffering permanent
any chemical
transformation[10]'
efficiency this Dyesensitized
overall of AM1'5(Air
solarcell is 7% under
The reported
mass1.5)f6l [7t.
TheAMl.Sconversionpowerefficiency1lAMl.sofaphotovoltaicdeviceisgivenb
n
no*'"=P-ffm=FFv**
where
-- v.i,""
-
,-l'=-
v*J*
wherePo,uristheoutpute|ectricalpowerofthedeviceunderil|umination,Prnist
incident the deviceas measured a calibrated
on by reference cell' %" is the
intensity
cunent denslty;m is the spectral
ooen circuitvoftale, and Js" is the short-circuit
mismatch factorthat accounts deviations the spectraloutputof the solarsimulator
for in
152
5. with respectto the standardAM1.5 spectrumand deviationsin the spectralresponseof
the deviceunder measurewith respectto that of the referencecell;FF is the fill factor.
novel deviceconceptshave been
Great effort has been made to improvethe efficiency:
developed,new materialshas been tested, different layer techniqueswhere applied.
Theseeffortsresulted an efficiency approximately [8] [11][12] lt appears
in of 11% that
for one decade now the efficiency of nano-structuredcells has been essentially
slagnating researchprogress.['13]
despitesignificant
though
We investigatedwith an alternativeapproach,the effects of the fundamental,
mostlyignored,processeslike sinteringand soakingthe anataseTiO2porouslayer, on
the IPCE.
printed
Screen
Figure lresoporous
2: TiO, Figure3: Dense Ti02
sputtered
Experimental
For the productionof substrates,we distinguishtwo types: the first substrates are
regular microscopeglasses,the second type are patternedFluorinedoped Tin Oxide
ConductiveOxide (TCO),which will act as a
(FTO) glasses.The latter is a Transparent
153
6. cathode,respectively anode in the DSSC.'TWopattemswere etched uslng
an
Iithography, with inter{igital structures otherwlth planesufaces' All substrate-s
one the
-de-ionizeA
were lhoroughly cleaned in soap water, rinsed Mth water, ultrasonically
rinsedIn Acetoneand boiledin lsopropanol, this to ensurea fat anddustfree substrate
for good adhesion.The FTO substtateswere sputtered in a home made sputter
installation establish denseTio2-antase
to a layer(seeFigure of approximately00nm
3) 1
thick and will act as a holeblocklnglayer'All subsfates werethen screenprinted a
with
@mmerdalTiO2paste,purchased from Solaronix. The pasteis dried and sinteredin a
fumaceto ensurepercolation the TiO2nanoparticles'
of
0.2nE Fusg+lbl€A
a
a
B
tr|drdrtrd
Ru-dyes Rr535 (C)Ru-s3s.bis
Figure 4: (A)Absorbance (B) TBA
The obtainedsampleswere then dividedin seven groupssach group containing ten
samoles. w€re immersed an
The substrates in gthanolsoluiioncontalning commercial
a
Ruthenium bas€ddye (seeFigure4). Foralt groups,concentration temperature the
or of
solution changed.
was
pure
Afrer time periods,variatingfrom th to 196h, all substrateswere rinsed wllh
ethanolto withdrawthe excEssof dye.The absorbance was measured usinga W-Vis
meter.
The cathodelayers(FTO)were sputtered with a thin (3onm)Platinum layer,whichwill
layerfor elecirondonation
act as a catalyzing to the elecfolyte' The anodeandcathode
7. are assembled with a hot meltspacer.The complete
together cellswere vacuumfilled
with an electrolyte,
consistedof 50m[.4tri-iodidein acetonitrile,
sealed and ready to be
tested.
Results
and Discussion
Annealing
Fluorinedoped Tin Oxide (FTO) substrates
were patterned that 25pm interdigital
so
structureswere obtained.These substraleswere screen-printedwith a TiO2paste and
annealed
whilein-situresistance wereconducted.
measurements
profiles,see Figure 5 and can be
This resultedin time vs. temperature/current
interpretedin such way that the ideal temperatureprofile can be produced to get
sufficient percolationwithout destroying the meso-porousnetwork. The ideal
profile incorporate different
temperature will the usedin the Ti02 pasteand the
materials
thesechemical
timeto burn-out binders
without
creating
cracksin the layer.Cracksdue
to a rapidheatingwill clearlybe shownin the measurement a suddendecrease
as in
conduction.
when an increase conduction followed
Percolation the nanocrystals observed
of is in is
by a slow decreasewherethe crystalsgrow.
best results are obtainedwhen the surface area availablefor dye
Theoretically,
chemisorption maximum
is while still havinga continues
network allowfor electron
to
conduction.
While plotting currentin function temperature,
the of plols can be made-By
Arrhenius
fittingthe activation modelcan be derived. this caseconduction
energya conduction ln
is governed thermal
by hopping
activated [14][15][16].
155
8. * T€mperd$.re pllltb
o Offial'r€flt
g
, g
E
I
6
g
for annealing TiO2
Figure5: Timevs.Temperature/Current of
?
l {r {av}
10Vand 100V)
Figura6: Arrhenius for annealing TiO2at several.voltage.s-(1v' line ths
plot of
and the thin solid
where the thick solid r,n" t"pt"""ni" the measurement
fit.
Arrhenius
Dye soaking
pholons
should be
Lightabsorption a key factorof solarcellssinceabsorbed
is
converted electrons. Sensitized
into Dye SolarCells(DSSC) soaked a dye
are in
Ru-based andsoabsorption betuned
dyes, can bythechosen dye'
typically
solution,
156
9. Adsorption
kinetics TiOzwere undertaken, determination dye concentration
for the of
was done with a UV-Visspectrometer measuring
by absorbance 1,a"(535nm).
at The
time profileof dye adsorption a singleand continues
is curve leadingto saturation,
suggesting the possiblemonolayercoverageof dye on the surfaceof TiOz. The
adsorptionexperiments
were conductedat varioustemperatures
C18oC,20oC and
37.50C)and at various concentrations
(0.8m9/ml,
0.2mg/mtand 0.02mg/ml).
The
amount of adsorptionvariationis shown. lt is seen that temperature significanfly
influencesthe adsorptioncapacity.High temperature results in high adsorption,
suggesting endothermic
an property.
The adsorption function timecan be fittedwitha pseudo
in of second-order
rate:
1 't 1.
i=ne q.'
qr (andqe)is the amount dye adsorbed TiO2at timet (andat equilibrium).is the
of on k
pseudosecond-order constant dye adsorption, is expressed a function
rate of it as of
temperature the Arrhenius-
by typerelationship
[17].
lnK=lnA-3
RT
IPCE
Incident
Photon current
to (IPCE)is a technique measure conversion
Efficiency to the of
incidentphotonsand the percentage those photonsthat effectively
of generated
an
electron. halogenlamp in combination
A with a monochromator used to produce
is
monochromatic
light.This light is passedthrougha beam splitter that the incident
so
lighton the samplesolarcellis known.
IPCEis determined [18]:
by
4pce = 1Lue Dcr ' lcce
qrne:Lightharvesting (amount absorbed
efficiency of photons)
qcrE:
Chargeinjection
efficiency
rtccE:
Chargecollection
efficiency
t57
10. + 37.5oC0.2m9/mlRu535
+ o.2mglml20qc Ftltes + Zo"Co.2mg/nrlRu535
+ 0.02mg/m120rc Ru535 ---- laoo 0.zmg/rnlnu535
+ 20'C R!535
o.8mgy'ml
-18'C0 2mg/mlRu535
2o6Co 2s€/ml Fu535
37.5"CO-2mSln Ru535
0.8 mg/ml20"C Ru535
c2 mg/ml2CfC8u535
o.o2 mg,'ml2o"c Ru535
3ff
S?lil?;^
*;ff ;:?:*"#:nU'""tJlHH*1.l"':':i's"JT.':i3
;,,ff
Belerence
Gall
Test Cdl
Monoafi€mator
(lPcE)testsetup
Photon currentEfficiency
Figure8r Incident
to
be
absorbtion'there should
on the rLHEby saturating dye
the
Since we focusedmainly "'"'nu showsthat
other parameter Frg::..n
without"n"ng;ng ;nv
an increasein lPcE will increase'
dye the efficiency DSSC's
of
by changing the amountof adsorDed
158
11. |lJ
Wav€lengdx{r:m}
Figure g: lpCE for DSSCas functionof soakinqtime
Conclusions
An effort has been made to increasethe Incidentphoton to
Current Efficiencyof Dye
Sensitized Solar Cells by focusing on the sinter process and
on the soaking time
process Positiveresurtswere obtainedby tuningthe sinteringprofirein such way that
a
conductive network of TiO2 was obtained without destroying
the pore size of the
mesoporousnetwork. These pores promote the active surface where
dye molecules
couldanchorand providea directchargeinjectionin the TiO2layer_
substrates were syslematicallyimmersed in solutionswith
differentconcentrationat
variabre temperaturesresurting a moderto describethe dye uptake.This resurted
in in a
positivechange of lpCE by a factor of 3. The proposed
approachthereforeresultedto
be efficienttowards a better understanding and improvementof dye sensitizedsolar
ce s-
159
12. Acknowledgements
Theauthor
likesto acknowledge universiteit
the Hasselt xios Hogeschool financial
/ for
support'Furthermore poryspec to the FWo
thanksis due to the rwr-sBo project an
(Phd.Koen Vandewal)
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[9] J. Nelson,
Physical Review phys.Rev.B pRB59, 15374
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