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Full-Text Articles in Physical Sciences and Mathematics

Modulation Of Electrocatalytic Activity By Tuning Anion Electronegativity: Case Study With Copper Chalcogenides, Harish Singh, David Prendergast, Manashi Nath Oct 2023

Modulation Of Electrocatalytic Activity By Tuning Anion Electronegativity: Case Study With Copper Chalcogenides, Harish Singh, David Prendergast, Manashi Nath

Chemistry Faculty Research & Creative Works

Anion-tuning in metallic chalcogenides has been shown to have a significant impact on their electrocatalytic ability for overall water splitting. In this article, copper-based chalcogenides (Cu2 X, X= O, S, Se, and Te) have been systematically studied to examine the effect of decreasing anion electronegativity and increasing covalency on the electrocatalytic performance. Among the copper chalcogenides, Cu2Te has the highest oxygen evolution reaction (OER) activity and can sustain high current density of 10 and 50 mA cm−2 for 12 h. The difference in intrinsic catalytic activity of these chalcogenide surfaces have been also probed through density functional theory calculations, which …


The Application Of Transition Metal Sulfide Nanomaterials And Their Composite Nanomaterials In The Electrocatalytic Reduction Of Co2: A Review, Jason Parsons, Mataz Alcoutlabi Feb 2023

The Application Of Transition Metal Sulfide Nanomaterials And Their Composite Nanomaterials In The Electrocatalytic Reduction Of Co2: A Review, Jason Parsons, Mataz Alcoutlabi

Chemistry Faculty Publications and Presentations

Electrocatalysis has become an important topic in various areas of research, including chemical catalysis, environmental research, and chemical engineering. There have been a multitude of different catalysts used in the electrocatalytic reduction of CO2, which include large classes of materials such as transition metal oxide nanoparticles (TMO), transition metal nanoparticles (TMNp), carbon-based nanomaterials, and transition metal sulfides (TMS), as well as porphyrins and phthalocyanine molecules. This review is focused on the CO2 reduction reaction (CO2RR) and the main products produced using TMS nanomaterials. The main reaction products of the CO2RR include carbon monoxide (CO), formate/formic acid (HCOO−/HCOOH), methanol (CH3OH), ethanol …


Inorganic Cesium Lead Mixed Halide Based Perovskite Solar Materials Modified With Functional Silver Iodide, Vincent Obiozo Eze, Lucas Braga Carani, Haimanti Majumder, M. Jasim Uddin, Okenwa Okoli May 2022

Inorganic Cesium Lead Mixed Halide Based Perovskite Solar Materials Modified With Functional Silver Iodide, Vincent Obiozo Eze, Lucas Braga Carani, Haimanti Majumder, M. Jasim Uddin, Okenwa Okoli

Chemistry Faculty Publications and Presentations

Inorganic CsPbIBr2 perovskites have recently attracted enormous attention as a viable alternative material for optoelectronic applications due to their higher efficiency, thermal stability, suitable bandgap, and proper optical absorption. However, the CsPbIBr2 perovskite films fabricated using a one-step deposition technique is usually comprised of small grain size with a large number of grain boundaries and compositional defects. In this work, silver iodide (AgI) will be incorporated as an additive into the CsPbIBr2 perovskite precursor solution to prepare the unique perovskite CsI(PbBr2)1-x(AgI)x. The AgI additive in the precursor solution works as a nucleation promoter which will help the perovskite to grow …


A Molecular Tetrahedral Cobalt-Seleno-Based Complex As An Efficient Electrocatalyst For Water Splitting, Ibrahim Munkaila Abdullahi, Jahangir Masud, Polydoros Chrisovalantis Ioannou, Eleftherios Ferentinos, Panayotis Kyritsis, Manashi Nath Feb 2021

A Molecular Tetrahedral Cobalt-Seleno-Based Complex As An Efficient Electrocatalyst For Water Splitting, Ibrahim Munkaila Abdullahi, Jahangir Masud, Polydoros Chrisovalantis Ioannou, Eleftherios Ferentinos, Panayotis Kyritsis, Manashi Nath

Chemistry Faculty Research & Creative Works

The cobalt-seleno-based coordination complex, [Co{(SePiPr2)2N}2], is reported with respect to its catalytic activity in oxygen evolution and hydrogen evolution reactions (OER and HER, respectively) in alkaline solutions. An overpotential of 320 and 630 mV was required to achieve 10 mA cm-2 for OER and HER, respectively. The overpotential for OER of this CoSe4-containing complex is one of the lowest that has been observed until now for molecular cobalt(II) systems, under the reported conditions. In addition, this cobalt-seleno-based complex exhibits a high mass activity (14.15 A g-1) and …


Molten Salt Synthesized Submicron Perovskite La1–Xsrxcoo3 Particles As Efficient Electrocatalyst For Water Electrolysis, Swati Mohan, Yuanbing Mao Sep 2020

Molten Salt Synthesized Submicron Perovskite La1–Xsrxcoo3 Particles As Efficient Electrocatalyst For Water Electrolysis, Swati Mohan, Yuanbing Mao

Chemistry Faculty Publications and Presentations

Perovskite oxides are an important and effective class of mixed oxides which play a significant role in the fields of energy storage and conversion systems. Here we present a series of cobaltite perovskite LaCoO3 particles which have been doped with 0, 5, 10, 20, and 30% of Sr2C and have been synthesized by a combined sol– gel and molten-salt synthesis procedure, which provides a regular morphology of the particles. These Sr2C-doped LaCoO3 particles have been characterized by powder X-ray diffraction, Raman spectroscopy, infrared spectroscopy, X-ray photoelectron spectroscopy, and scanning electron microscopy. Moreover, these Sr2C doped LaCoO3 particles have been demonstrated …


A Spin-Coated Tiox/Pt Nanolayered Anodic Catalyst For The Direct Formic Acid Fuel Cells, Islam M. Al-Akraa, Ahmad M. Mohammad Prof Jan 2020

A Spin-Coated Tiox/Pt Nanolayered Anodic Catalyst For The Direct Formic Acid Fuel Cells, Islam M. Al-Akraa, Ahmad M. Mohammad Prof

Chemical Engineering

The CO poisoning of the platinum anodic catalyst which typically functions the catalytic deterioration of the direct formic acid fuel cells could be minimized with a simple modification for Pt with titanium oxide. The fabrication scheme involved the spin-coating of a Ti precursor onto a Pt thin layer that was physically sputtered onto a Si substrate. The whole assembly was subjected to a post-annealing processing to produce the TiOx layer (60 nm) in a porous structure (mostly Anatase) atop of the Pt surface. The porous nature of the TiOx layer permitted the participation of Pt in the electrocatalysis of the …


Electronic Structure Engineering Of Licoo2 Toward Enhanced Oxygen Electrocatalysis, Xiaobo Zheng, Yaping Chen, Xusheng Zheng, Guoqiang Zhao, Kun Rui, Peng Li, Xun Xu, Zhenxiang Cheng, Shi Xue Dou, Wenping Sun Jan 2019

Electronic Structure Engineering Of Licoo2 Toward Enhanced Oxygen Electrocatalysis, Xiaobo Zheng, Yaping Chen, Xusheng Zheng, Guoqiang Zhao, Kun Rui, Peng Li, Xun Xu, Zhenxiang Cheng, Shi Xue Dou, Wenping Sun

Australian Institute for Innovative Materials - Papers

Developing low-cost and efficient electrocatalysts for the oxygen evolution reaction and oxygen reduction reaction is of critical significance to the practical application of some emerging energy storage and conversion devices (e.g., metal-air batteries, water electrolyzers, and fuel cells). Lithium cobalt oxide is a promising nonprecious metal-based electrocatalyst for oxygen electrocatalysis; its activity, however, is still far from the requirements of practical applications. Here, a new LiCoO 2 -based electrocatalyst with nanosheet morphology is developed by a combination of Mg doping and shear force-assisted exfoliation strategies toward enhanced oxygen reduction and evolution reaction kinetics. It is demonstrated that the coupling effect …


Fabrication Of Cuox-Pd Nanocatalyst Supported On A Glassy Carbon Electrode For Enhanced Formic Acid Electro-Oxidation, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof Jan 2018

Fabrication Of Cuox-Pd Nanocatalyst Supported On A Glassy Carbon Electrode For Enhanced Formic Acid Electro-Oxidation, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof

Chemical Engineering

Formic acid (FA) electro-oxidation (FAO) was investigated at a binary catalyst composed of palladium nanoparticles (PdNPs) and copper oxide nanowires (CuOxNWs) and assembled onto a glassy carbon (GC) electrode. /e deposition sequence of PdNPs and CuOxNWs was properly adjusted in such a way that could improve the electrocatalytic activity and stability of the electrode toward FAO. Several techniques including cyclic voltammetry, chronoamperometry, field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction were all combined to report the catalyst’s activity and to evaluate its morphology, composition, and structure. /e highest catalytic activity and stability were obtained at the CuOx/Pd/GC …


Kinetic Study Of The Oxygen Reduction Reaction On Α-Ni(Oh)2 And Α-Ni(Oh)2 Supported On Graphene Oxide, Elaheh Farjami, L. Jay Deiner Jun 2015

Kinetic Study Of The Oxygen Reduction Reaction On Α-Ni(Oh)2 And Α-Ni(Oh)2 Supported On Graphene Oxide, Elaheh Farjami, L. Jay Deiner

Publications and Research

The kinetics of the oxygen reduction reaction on α-Ni(OH)2 and α-Ni(OH)2 supported on graphene oxide (α-Ni(OH)2/GO) were investigated using rotating disk linear sweep voltammetry in alkaline solutions of varying oxygen and hydroxyl concentrations. Over the full hydroxyl concentration range (0.05 M to 0.5M), α-Ni(OH)2/GO displayed higher activity than unsupported α-Ni(OH)2. The electron transfer numbers were 2.9 ± 0.2 for α-Ni(OH)2, 3.4 ± 0.1 for α-Ni(OH)2/GO at low [OH−], and 3.8–3.9 for α-Ni(OH)2/GO at high [OH−]. Compared to α-Ni(OH)2, α-Ni(OH)2/GO displayed higher chemical reaction rate constants and higher electron transfer rate constants. These differences suggest that the synergy between the α-Ni(OH)2 …


On The Catalytic Activity Of Palladium Nanoparticles-Based Anodes Towards Formic Acid Electro-Oxidation: Effect Of Electrodeposition Potential, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof Jan 2015

On The Catalytic Activity Of Palladium Nanoparticles-Based Anodes Towards Formic Acid Electro-Oxidation: Effect Of Electrodeposition Potential, Islam M. Al-Akraa Dr., Ahmad M. Mohammad Prof, Mohamed S. El-Deab Prof, Bahgat E. El-Anadouli Prof

Chemical Engineering

In this investigation, the catalytic activity of palladium nanoparticles (PdNPs)-modified glassy carbon (GC) (simply noted as PdNPs/GC) electrodes towards the formic acid electro-oxidation (FAO) was investigated. The deposition of PdNPs on the GC substrate was carried out by a potentiostatic technique at different potentials and the corresponding influence on the particles size and crystal structure of PdNPs as well as the catalytic activity towards FAO was studied. Scanning electron microscopy (SEM) demonstrated the deposition of PdNPs in spherical shapes and the average particle size of PdNPs deposited at a potential of 0 V vs. Ag/AgCl/KCl(sat.) was the smallest (ca. 8 …