By creating a hydrophobic electrode surface, the competing hydrogen evolution reaction can be drastically reduced, which can dramatically enhance the performance of the electrochemical CO2 reduction.
By creating a hydrophobic electrode surface, the competing hydrogen evolution reaction can be drastically reduced, which can dramatically enhance the performance of the electrochemical CO2 reduction.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
Selective Cellobiose Photoreforming for Simultaneous Gluconic Acid and Syngas...Pawan Kumar
Here, we demonstrate the selective cellobiose (building block of cellulose) photoreforming for gluconic acid and syngas co-production in acidic conditions by rationally designing a bifunctional polymeric carbon nitride (CN) with potassium/sulfur co-dopant. This heteroatomic doped CN photocatalyst possesses enhanced visible light absorption, higher charge separation efficiency than pristine CN. Under acidic conditions, cellobiose is not only more efficiently hydrolyzed into glucose but also promotes the syngas and gluconic acid production. Density functional theory (DFT) calculations reveal the favorable generation of •O2− during the photocatalytic reaction, which is essential for gluconic acid production. Consequently, the fine-designed photocatalyst presents excellent cellobiose conversion (>80%) and gluconic acid selectivity (>70%) together with the co-production of syngas (~56 μmol g-1 h-1) under light illumination. The current work demonstrates the feasibility of biomass photoreforming with value-added chemicals and syngas co-production under mild condition.
Lobanov - Nb-sputtered 150 MHz Quarter-wave Resonators for ANU Linac Upgradethinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Nb sputtered 150 MHz quarter-wave resonators for ANU LINAC Upgrade (Nikolai Lobanov - 20')
Speaker: Nikolai Lobanov - The Australian National University | Duration: 20 min.
Enhancement of Structure, Tc and Irreversibility Line in High Tc Superconduct...IJERA Editor
AC susceptibility (ac= ’+ i‖) and X ray diffraction (XRD) are very useful for characterizing high Tc superconductors. We report here on the preparation, X-ray diffraction with Rietveld refinement, resistivity , AC magnetic susceptibility measurements and effect of heat treatments in (Y1-xNdx)SrBaCu3O6+z. Each sample was subject to two types of heat treatment: oxygen annealing [O] and argon annealing followed by oxygen annealing [AO]. For each x, the [AO] heat treatment increases the orthorhombicity ε = (b-a)/(b+a) (for 0≤x<1),>0.2), the distance d[Cu(1)-(Sr/Ba)] (for x<0.25)>0.25; increase in cationic and chain oxygen ordering; psh and in-phase purity for the [AO] samples may account for the observed data.
Electrochemical CO2 reduction reaction (eCO2RR) is performed on two
intermetallic compounds formed by copper and gallium metals (CuGa2
and Cu9Ga4). Among them, CuGa2 selectively converts CO2 to methanol
with remarkable Faradaic efficiency of 77.26% at an extremely low potential of −0.3 V vs RHE. The high performance of CuGa2 compared to
Cu9Ga4 is driven by its unique 2D structure, which retains surface and
subsurface oxide species (Ga2O3) even in the reduction atmosphere. The
Ga2O3 species is mapped by X-ray photoelectron spectroscopy (XPS) and
X-ray absorption fine structure (XAFS) techniques and electrochemical
measurements. The eCO2RR selectivity to methanol are decreased at
higher potential due to the lattice expansion caused by the reduction of
the Ga2O3, which is probed by in situ XAFS, quasi in situ powder X-ray
diffraction, and ex situ XPS measurements. The mechanism of the formation of methanol is visualized by in situ infrared (IR) spectroscopy and the
source of the carbon of methanol at the molecular level is confirmed from
the isotope-labeling experiments in presence of 13CO2. Finally, to minimize
the mass transport limitations and improve the overall eCO2RR performance, a poly(tetrafluoroethylene)-based gas diffusion electrode is used in
the flow cell configuration.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
International Journal of Research in Engineering and Science is an open access peer-reviewed international forum for scientists involved in research to publish quality and refereed papers. Papers reporting original research or experimentally proved review work are welcome. Papers for publication are selected through peer review to ensure originality, relevance, and readability.
Selective Cellobiose Photoreforming for Simultaneous Gluconic Acid and Syngas...Pawan Kumar
Here, we demonstrate the selective cellobiose (building block of cellulose) photoreforming for gluconic acid and syngas co-production in acidic conditions by rationally designing a bifunctional polymeric carbon nitride (CN) with potassium/sulfur co-dopant. This heteroatomic doped CN photocatalyst possesses enhanced visible light absorption, higher charge separation efficiency than pristine CN. Under acidic conditions, cellobiose is not only more efficiently hydrolyzed into glucose but also promotes the syngas and gluconic acid production. Density functional theory (DFT) calculations reveal the favorable generation of •O2− during the photocatalytic reaction, which is essential for gluconic acid production. Consequently, the fine-designed photocatalyst presents excellent cellobiose conversion (>80%) and gluconic acid selectivity (>70%) together with the co-production of syngas (~56 μmol g-1 h-1) under light illumination. The current work demonstrates the feasibility of biomass photoreforming with value-added chemicals and syngas co-production under mild condition.
Lobanov - Nb-sputtered 150 MHz Quarter-wave Resonators for ANU Linac Upgradethinfilmsworkshop
http://www.surfacetreatments.it/thinfilms
Nb sputtered 150 MHz quarter-wave resonators for ANU LINAC Upgrade (Nikolai Lobanov - 20')
Speaker: Nikolai Lobanov - The Australian National University | Duration: 20 min.
Enhancement of Structure, Tc and Irreversibility Line in High Tc Superconduct...IJERA Editor
AC susceptibility (ac= ’+ i‖) and X ray diffraction (XRD) are very useful for characterizing high Tc superconductors. We report here on the preparation, X-ray diffraction with Rietveld refinement, resistivity , AC magnetic susceptibility measurements and effect of heat treatments in (Y1-xNdx)SrBaCu3O6+z. Each sample was subject to two types of heat treatment: oxygen annealing [O] and argon annealing followed by oxygen annealing [AO]. For each x, the [AO] heat treatment increases the orthorhombicity ε = (b-a)/(b+a) (for 0≤x<1),>0.2), the distance d[Cu(1)-(Sr/Ba)] (for x<0.25)>0.25; increase in cationic and chain oxygen ordering; psh and in-phase purity for the [AO] samples may account for the observed data.
Electrochemical CO2 reduction reaction (eCO2RR) is performed on two
intermetallic compounds formed by copper and gallium metals (CuGa2
and Cu9Ga4). Among them, CuGa2 selectively converts CO2 to methanol
with remarkable Faradaic efficiency of 77.26% at an extremely low potential of −0.3 V vs RHE. The high performance of CuGa2 compared to
Cu9Ga4 is driven by its unique 2D structure, which retains surface and
subsurface oxide species (Ga2O3) even in the reduction atmosphere. The
Ga2O3 species is mapped by X-ray photoelectron spectroscopy (XPS) and
X-ray absorption fine structure (XAFS) techniques and electrochemical
measurements. The eCO2RR selectivity to methanol are decreased at
higher potential due to the lattice expansion caused by the reduction of
the Ga2O3, which is probed by in situ XAFS, quasi in situ powder X-ray
diffraction, and ex situ XPS measurements. The mechanism of the formation of methanol is visualized by in situ infrared (IR) spectroscopy and the
source of the carbon of methanol at the molecular level is confirmed from
the isotope-labeling experiments in presence of 13CO2. Finally, to minimize
the mass transport limitations and improve the overall eCO2RR performance, a poly(tetrafluoroethylene)-based gas diffusion electrode is used in
the flow cell configuration.
Lattice anchoring between colloidal crystal and perovskite semiconductor stabilizes can be a useful strategy for a stable semiconductor interface for solar cell application
Ni-doping can substantially increase the p[erformance of electrochemical water splitting in the case of WC or MoC lattice. In situ XAFS shows the charge transfer between Ni and W/Mo which is the origin of better HER/OER performance in the wide pH range of electrolytes.
Electrochemical CO2 reduction in acidic media is advantageous as the loss of carbonate formation (in alkaline media) is less and the current density is also high. The main goal is to suppress the competing hydrogen evolution reaction by careful optimization of electrode-electrolyte interface design.
How to Create Map Views in the Odoo 17 ERPCeline George
The map views are useful for providing a geographical representation of data. They allow users to visualize and analyze the data in a more intuitive manner.
The Art Pastor's Guide to Sabbath | Steve ThomasonSteve Thomason
What is the purpose of the Sabbath Law in the Torah. It is interesting to compare how the context of the law shifts from Exodus to Deuteronomy. Who gets to rest, and why?
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Students, digital devices and success - Andreas Schleicher - 27 May 2024..pptxEduSkills OECD
Andreas Schleicher presents at the OECD webinar ‘Digital devices in schools: detrimental distraction or secret to success?’ on 27 May 2024. The presentation was based on findings from PISA 2022 results and the webinar helped launch the PISA in Focus ‘Managing screen time: How to protect and equip students against distraction’ https://www.oecd-ilibrary.org/education/managing-screen-time_7c225af4-en and the OECD Education Policy Perspective ‘Students, digital devices and success’ can be found here - https://oe.cd/il/5yV
The Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
This is a presentation by Dada Robert in a Your Skill Boost masterclass organised by the Excellence Foundation for South Sudan (EFSS) on Saturday, the 25th and Sunday, the 26th of May 2024.
He discussed the concept of quality improvement, emphasizing its applicability to various aspects of life, including personal, project, and program improvements. He defined quality as doing the right thing at the right time in the right way to achieve the best possible results and discussed the concept of the "gap" between what we know and what we do, and how this gap represents the areas we need to improve. He explained the scientific approach to quality improvement, which involves systematic performance analysis, testing and learning, and implementing change ideas. He also highlighted the importance of client focus and a team approach to quality improvement.
3. Morphological evolution of the CuNCs during electrolysis. a–c Representative CuNCs of three different
sizes: a 16 nm, b 41 nm, and c 65 nm, imaged with TEM at different operation times. The rectangle in a
encloses an aggregated assembly of particles. The red and yellow arrows in b indicate small clusters and
broken CuNCs, respectively. Scale bars: 100 nm
Characterization of the nanoclusters during CO2-ER
4. Characterizations of the Cu nanoclusters formed during electrolysis. a–e of a, b Cu nanoclusters (<3 nm) and
c–e Cu nanoparticles (~5 nm) formed from the 41 nm CuNCs during electrolysis for 4.5 h under CO2RR
conditions. Circles in a, b, and c enclose regions containing nanoclusters and nanoparticles, respectively. e is
a high-magnification view of the region boxed in d. f FFT of the HR-STEM image shown in e. Simulated
electron diffraction pattern (blue rings: ring sampling diffraction planes; red spectrum: intensity profile) of
Cu are included for reference. Scale bars: a 3 nm, b, c, e 5 nm, d 50 nm, and f 5 nm−1
High-resolution HAADF-STEM images
5. Electrocatalytic performance over time of the CuNCs.
a–c Faradaic efficiency of gaseous products and current
density from CuNCs of three different sizes: a 16 nm, b
41 nm, c 65 nm, collected during a 12 h-course of
CO2RR. Shaded areas of each line show standard
deviations from three independent measurements
Impact of the morphological changes on the CO2RR performance.
6. Impact of the morphological changes on the CO2RR performance.
Gaseous products of CO2RR. a-c Faradaic
efficiencies of gaseous products, i.e., C2H4,
CH4 and CO, for a 16, b 41 and c 65 nm
CuNCs over a 12 h-course of CO2RR.
Shaded areas of each line show standard
deviations from three independent
measurements.
7. Crystalline facets and degradation pathway. a Top, HR-TEM image of one 41 nm CuNC along the [001]
crystallographic direction; Bottom, an enlarged view of the region marked in the top panel. The inset shows
the fast Fourier transformation (FFT) of the HR-TEM image. b TEM images and corresponding
morphological models of one CuNC along two crystallographic directions, [001] and [111], from left to right.
c, d TEM image of one CuNC electrolyzed for c 1 h and d 3 h. The arrows point to the positions where the
degradations take place. e Tomographic reconstruction of the CuNCs and f corresponding schematic
morphological models at different stages during a 12 h-course of CO2RR. Scale bars: 10 nm
Atomic-scale analysis of the structural degradation
8. The effect of CO2 and negative potential on nanolcustering. a, b TEM images of 41 nm CuNCs that were
collected from control experiments running for a 12 h and b 3 h, in which a negative potential and b CO2 was
cut off, respectively, and other conditions were identical to those typical for CO2RR. In the contre experiment
designed for examining the effect of negative potential, the electrolyte (i.e., KHCO3 solution) was bubbled
with N2 overnight to completely remove dissolved CO2. Under the negative potential applied, therefore, only
H2 was produced. As can be seen from the two images, sole CO2 adsorption has very trivial effect on inducing
nanoclustering, while sole negative potential contributes majorly to the nanoclustering observed in Cu
nanoparticles during CO2RR. Scale bars: 50 nm.
9. a, b Grand potential interface energies for a H-covered and b CO-covered Cu surfaces in aqueous
solution.
c pH and potential dependence of the Wulff-shape of Cu nanoparticles including H, CO, and mixed
H + CO covered surfaces. The cubicity is defined as the relative contribution of Cu (100) surfaces to the
Wulff-shape. The cubicity of the polyhedron defined by (100), (110), and (111) facets under realistic
CO2RR conditions decreases as the potential decreases.
Theoretical DFT investigations
Thermodynamic stability
H + CO covered surfaces
γ110 > γ100 > γ111 to γ100 > γ110 > γ111
Clean surfaces
10. For potentials larger than -0.4 V Cu(111) and Cu(100) are predominantly covered with CO.
The suppression of H evolution due to site blocking of CO has been reported
experimentally
More negative potentials induce H/CO adsorption which in turn drives the electron
transfer from the electrode toward the electrochemical interface built-up by the
adsorbing species, and as a result, a strong reduction of interface free energies for fully
covered surfaces
Surface Pourbaix diagram
11. Dissolution of CuNCs by a voltage. TEM images of CuNCs that were deposited on TEM Cu grids and directly
applied with a voltage of -1.1 V under ambient conditions for varied operation times up to 12 h, showing that
CuNCs were broken up into nanoclusters. Scale bars: 100 nm.
TEM images were collected after electrolysis under typical CO2RR conditions for 12 h, at a potential of
a -1.1 V, b -0.7 V, and c -0.3 V vs. RHE, showing less degradation of CuNCs at more positive potentials.
12. Overview of the degradation mechanism of CuNCs during CO2RR.
Theory points out that the adsorption of either H- or CO- species on the crystal surface eventually
induces degradation of the crystals under a sufficiently negative potential.
Higher catalytic activity implies higher adsorbate coverage thus faster degradation. The 16 nm CuNCs
are much more reactive and selective for HER than bigger particles.
For the 41 nm CuNCs, the nanoclustering starts at the intersection between the {110} and the {100}
facets, previously identified as the catalytic sites favoring CO2RR over HER.
This leads to the assumption that CO-adsorbates combined with the negative potential are driving the
degradation.
The simultaneous phenomena of the reduction in size of the CuNCs, the increased cluster population
and the ligand removal over time induce the formation of aggregated assemblies as the size drops
tendency to sintering to minimize surface energy and the mobility of the nanoparticles increase
13. TEM images after electrolysis at -1.1 V and -1.7 V vs RHE, respectively, for 2 h, showing that
nanoclustering also occurs in Ag- and Pd based electrocatalysts. Here, the voltage applied for Pd nanocubes
was a bit more negative than normal ones employed CO2RR. For the Pd nanocubes, nanoclustering was
observed at -1.7 V vs RHE instead of -1.1 V. This behaviour depends on the system-dependent energetics.
Nevertheless, it proves the generality of potential-induced nano clustering in metallic electrocatalysts. Scale
bars:100 nm.
Extension of nanoclustering to
Ag nanocubes and Pd nanocubes
14. Summary
An unusual nanoclustering degradation mechanism for nanoparticle electrocatalysts been
reported.
The CO2 adsorption and the negative potentials were identified as the parameters
accounting for the nanoclustering, with the latter outweighing the former.
Strategies for preserving Cu electrocatalyst nanostructures:
By introduction of suitable promoters (metal oxides, ligands, or another metal) that can
reduce the overpotential of Cu electrocatalysts toward CO2RR through mutual
interaction at the interface.
By wrapping the catalysts with a thin, porous, and conductive material, such as a
graphene oxide, can offer a good solution by physically impeding the detachment of
clusters from the catalyst while still preserves the necessary conductivity and CO2
accessibility to the active sites
15.
16.
17. XRD, XPS, and XANES, it was found that C2H4 production was favored on the catalysts containing mixed
oxidized copper species along with high oxygen content, while a sharp increase of CH4 production was
observed when Cu2+ disappeared on the surface.