Read by QxMD icon Read

copper water splitting

Yang Yang, Di Xu, Qingyong Wu, Peng Diao
Solar powered hydrogen evolution reaction (HER) is one of the key reactions in solar-to-chemical energy conversion. It is desirable to develop photocathodic materials that exhibit high activity toward photoelectrochemical (PEC) HER at more positive potentials because a higher potential means a lower overpotential for HER. In this work, the Cu2O/CuO bilayered composites were prepared by a facile method that involved an electrodeposition and a subsequent thermal oxidation. The resulting Cu2O/CuO bilayered composites exhibited a surprisingly high activity and good stability toward PEC HER, expecially at high potentials in alkaline solution...
October 17, 2016: Scientific Reports
Shengsheng Cui, Manman Qian, Xiang Liu, Zijun Sun, Pingwu Du
Scalable and robust catalysts for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) are required for the implementation of water splitting technologies as a globally applicable method of producing renewable hydrogen. Herein, we report nitrogen-enriched porous carbon materials containing copper/copper oxide, derived from copper porphyrin-based conjugated mesoporous polymers (CMPs), as a bifunctional catalyst for both HER and OER. These catalysts have a high surface area, unique tubular structure, and strong synergistic effect of copper/copper oxide and porous carbons, resulting in excellent performance for water splitting...
September 8, 2016: ChemSusChem
Tomasz Baran, Szymon Wojtyła, Cristina Lenardi, Alberto Vertova, Paolo Ghigna, Elisabetta Achilli, Martina Fracchia, Sandra Rondinini, Alessandro Minguzzi
Light-driven water splitting is one of the most promising approaches for using solar energy in light of more sustainable development. In this paper, a highly efficient p-type copper(II) oxide photocathode is studied. The material, prepared by thermal treatment of CuI nanoparticles, is initially partially reduced upon working conditions and soon reaches a stable form. Upon visible-light illumination, the material yields a photocurrent of 1.3 mA cm(-2) at a potential of 0.2 V vs a reversible hydrogen electrode at mild pH under illumination by AM 1...
August 24, 2016: ACS Applied Materials & Interfaces
Ting-Ting Li, Yue-Qing Zheng
The development of viable molecular water oxidation catalysts is an important issue in the conversion of electricity or solar fuel into chemical fuels via water splitting, and copper complexes have become promising candidates for catalyzing water oxidation because of their low cost, well-defined redox properties and relatively high reactivity. Herein, we describe the first tetranuclear Cu(ii)-based water oxidation catalyst: [Cu4(bpy)4(μ2-OH)2(μ3-OH)2(H2O)2](2+). The complex comprises a chair-like Cu4O4 core with aqua and bridging μ-hydroxo ligands, and the multinuclear core is expected to be advantageous for promoting multi-electron transfer...
August 9, 2016: Dalton Transactions: An International Journal of Inorganic Chemistry
María Isabel Díez-García, Teresa Lana-Villarreal, Roberto Gómez
Studies on water-splitting p-type oxide electrodes based on nontoxic earth-abundant elements are scarce. Herein, the behavior of electrodes composed of CuFe2 O4 nanoparticles 30 nm in size is presented. The as-prepared CuFe2 O4 nanoporous electrodes exhibit small anodic photocurrents in 0.1 m NaOH. However, an electrochemical pretreatment consisting in the application of sufficiently positive potentials leads to p-type behavior with a photocurrent onset as high as 1.1 V versus the reversible hydrogen electrode, which is among the most positive values reported for an oxide absorbing visible light (band gap of 2...
June 22, 2016: ChemSusChem
Dianyi Hu, Peng Diao, Di Xu, Mengyang Xia, Yue Gu, Qingyong Wu, Chao Li, Shubin Yang
We report the preparation of CuWO4 nanoflake (NF) array films by using a solid phase reaction method in which WO3 NFs were employed as sacrificial templates. The SEM, TEM and XRD results demonstrated that the obtained CuWO4 films possessed a network structure that was composed of single crystalline NFs intersected with each other. The CuWO4 NF films showed superior photoelectrochemical (PEC) activity to other CuWO4 photoanodes reported recently for the oxygen evolution reaction (OER). We attributed the high activity to the unique morphological and crystalline structure of the CuWO4 film, which enhanced the photoactivity by providing a large specific area, a short hole transport distance from the inside of CuWO4 to the CuWO4/solution interface, and a low grain boundary density...
March 21, 2016: Nanoscale
Anita Rakić, Nives Štambuk-Giljanović
The purpose of this study was to evaluate the prevalence of Legionella spp. and compare the quality of hot water between four facilities for accommodation located in Southern Croatia (the Split-Dalmatian County). The research included data collection on the technical and technological characteristics in the period from 2009 to 2012. The survey included a type of construction material for the distribution and internal networks, heating system water heater type, and water consumption. Changes in water quality were monitored by determination of the physical and chemical parameters (temperature, pH, free chlorine residual concentrations, iron, zinc, copper and manganese) in the samples, as well as the presence and concentration of bacteria Legionella spp...
February 2016: Environmental Monitoring and Assessment
Wooseok Yang, Yunjung Oh, Jimin Kim, Hyunchul Kim, Hyunjung Shin, Jooho Moon
Although copper-based chalcopyrite materials such as CuInS2 have been considered promising photocathodes for solar water splitting, the fabrication route for a nanostructure with vertical orientation has not yet been developed. Here, a fabrication route for vertically aligned CuInS2 nanorod arrays from an aqueous solution using anodic aluminum oxide template-assisted growth and transfer is presented. The nanorods exhibit a phase-pure CuInS2 chalcopyrite structure and cathodic photocurrent response without co-catalyst loading...
January 13, 2016: ACS Applied Materials & Interfaces
Katarzyna Skorupska, Paul A Maggard, Rainer Eichberger, Klaus Schwarzburg, Paria Shahbazi, Brandon Zoellner, Bruce A Parkinson
High-throughput combinatorial methods have been useful in identifying new oxide semiconductors with the potential to be applied to solar water splitting. Most of these techniques have been limited to producing and screening oxide phases formed at temperatures below approximately 550 °C. We report the development of a combinatorial approach to discover and optimize high temperature phases for photoelectrochemical water splitting. As a demonstration material, we chose to produce thin films of high temperature CuNb oxide phases by inkjet printing on two different substrates: fluorine-doped tin oxide and crystalline Si, which required different sample pyrolysis procedures...
December 14, 2015: ACS Combinatorial Science
Michael J Colaneri, Simon J Teat, Jacqueline Vitali
Electron paramagnetic resonance and crystallographic studies of copper-doped cadmium dl-histidine, abbreviated as CdDLHis, were undertaken to gain further understanding on the relationship between site structure and dynamic behavior in biological model complexes. X-ray diffraction measurements determined the crystal structure of CdDLHis at 100 and 298 K. CdDLHis crystallizes in the monoclinic space group P21/c with two cadmium complexes per asymmetric unit. In each complex, the Cd is hexacoordinated to two histidine molecules...
November 12, 2015: Journal of Physical Chemistry. A
Ilan Jen-La Plante, Ayelet Teitelboim, Iddo Pinkas, Dan Oron, Taleb Mokari
The formation of donor/acceptor junctions in hybrid nanomaterials is predicted to enhance photocatalytic activity as compared to single-component semiconductor systems. Specifically, nanomaterials containing a junction of n-type cadmium sulfide (CdS) and p-type copper sulfide (Cu2S) formed via cation exchange have been proposed as potential photocatalysts for reactions such as water splitting. Herein, we study the elemental distribution of Cu within these nanostructures using analytical transmission electron microscopy techniques...
February 6, 2014: Journal of Physical Chemistry Letters
Yang Li, Néstor Guijarro, Xiaoli Zhang, Mathieu S Prévot, Xavier A Jeanbourquin, Kevin Sivula, Hong Chen, Yongdan Li
Nanostructuring hematite films is a critical step for enhancing photoelectrochemical performance by circumventing the intrinsic limitations on minority carrier transport. Herein, we present a novel sol-gel approach that affords nanostructured hematite films by including CuO as sacrificial templating agent. First, by annealing in air at 450 °C a film comprising an intimate mixture of CuO and Fe2O3 nanoparticles is obtained. The subsequent treatment with NaCl and annealing at 700 °C under Argon reveals a nanostructured highly crystalline hematite film devoid of copper...
August 12, 2015: ACS Applied Materials & Interfaces
Minghao Xie, Shiqi Ai, Jian Yang, Yudi Yang, Yihan Chen, Yong Jin
In this study, AgCuZn sulfide is fabricated on the surface of AgCuZn alloys by hydrothermal sulfuration. This ternary metal sulfide is equipped with enhanced activity toward oxygen evolution reaction (OER) in an alkaline electrolyte. Through comparison of the alloys with diverse compositions, we find out the best electrochemical property of a particular alloy sulfide forming on a AgCuZn substrate (Ag:Cu:Zn=43:49:8). The alloy sulfide exhibits an onset overpotential (η) of 0.27 V with a Tafel slope of 95±2 mV dec(-1) and a current density of 130 mA cm(-2) at η of 0...
August 12, 2015: ACS Applied Materials & Interfaces
Sundaram Ganesh Babu, Ramalingam Vinoth, Dharani Praveen Kumar, Muthukonda V Shankar, Hung-Lung Chou, Kizhanipuram Vinodgopal, Bernaurdshaw Neppolian
Herein we report simple, low-cost and scalable preparation of reduced graphene oxide (rGO) supported surfactant-free Cu2O-TiO2 nanocomposite photocatalysts by an ultrasound assisted wet impregnation method. Unlike the conventional preparation techniques, simultaneous reduction of Cu(2+) (in the precursor) to Cu(+) (Cu2O), and graphene oxide (GO) to rGO is achieved by an ultrasonic method without the addition of any external reducing agent; this is ascertained by X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses...
May 7, 2015: Nanoscale
Divya Bohra, Wilson A Smith
Photoelectrochemical (PEC) water splitting offers a clean pathway to renewable and sustainable energy in the near future. The key to improving the efficiency of PEC devices is the ability to find materials with suitable optoelectronic properties, and identifying, then overcoming their limitations. In this paper, we explore the photoelectrochemical performance of CuWO4 photoanodes for solar water splitting, and find that charge separation is the dominant limitation for this material. As a result, we attempt to dope the material with Fe, the first such example of doping this semiconductor for PEC water splitting...
April 21, 2015: Physical Chemistry Chemical Physics: PCCP
Hao Bin Wu, Bao Yu Xia, Le Yu, Xin-Yao Yu, Xiong Wen David Lou
Electrochemical water splitting has been considered as a promising approach to produce clean and sustainable hydrogen fuel. However, the lack of high-performance and low-cost electrocatalysts for hydrogen evolution reaction hinders the large-scale application. As a new class of porous materials with tunable structure and composition, metal-organic frameworks have been considered as promising candidates to synthesize various functional materials. Here we demonstrate a metal-organic frameworks-assisted strategy for synthesizing nanostructured transition metal carbides based on the confined carburization in metal-organic frameworks matrix...
2015: Nature Communications
Vivek Sharma, Giray Enkavi, Ilpo Vattulainen, Tomasz Róg, Mårten Wikström
Molecular oxygen acts as the terminal electron sink in the respiratory chains of aerobic organisms. Cytochrome c oxidase in the inner membrane of mitochondria and the plasma membrane of bacteria catalyzes the reduction of oxygen to water, and couples the free energy of the reaction to proton pumping across the membrane. The proton-pumping activity contributes to the proton electrochemical gradient, which drives the synthesis of ATP. Based on kinetic experiments on the O-O bond splitting transition of the catalytic cycle (A → P(R)), it has been proposed that the electron transfer to the binuclear iron-copper center of O2 reduction initiates the proton pump mechanism...
February 17, 2015: Proceedings of the National Academy of Sciences of the United States of America
Jingshan Luo, S David Tilley, Ludmilla Steier, Marcel Schreier, Matthew T Mayer, Hong Jin Fan, Michael Grätzel
Though Cu2O has demonstrated high performance as a photocathode for solar water splitting, its band gap is too large for efficient use as the bottom cell in tandem configurations. Accordingly, copper chalcopyrites have recently attracted much attention for solar water splitting due to their smaller and tunable band gaps. However, their fabrication is mainly based on vacuum evaporation, which is an expensive and energy consuming process. Here, we have developed a novel and low-cost solution fabrication method, and CuInS2 was chosen as a model material due to its smaller band gap compared to Cu2O and relatively simple composition...
February 11, 2015: Nano Letters
Deniss Klauson, Olga Budarnaja, Ignacio Castellanos Beltran, Marina Krichevskaya, Sergei Preis
Photocatalytic water splitting for hydrogen and oxygen production requires sacrificial electron donors, for example, organic compounds. Titanium dioxide catalysts doped with platinum, cobalt, tungsten, copper and iron were experimentally tested for the production of hydrogen, oxygen and low molecular weight hydrocarbons from aqueous solutions of humic substances (HS). Platinum-doped catalyst showed the best results in hydrogen generation, also producing methane, ethene and ethane, whereas the best oxygen production was exhibited by P25, followed by copper--and cobalt-containing photocatalysts...
September 2014: Environmental Technology
Carlos G Morales-Guio, Xile Hu
Providing energy for a population projected to reach 9 billion people within the middle of this century is one of the most pressing societal issues. Burning fossil fuels at a rate and scale that satisfy our near-term demand will irreversibly damage the living environment. Among the various sources of alternative and CO2-emission-free energies, the sun is the only source that is capable of providing enough energy for the whole world. Sunlight energy, however, is intermittent and requires an efficient storage mechanism...
August 19, 2014: Accounts of Chemical Research
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"