Read by QxMD icon Read

Solar water oxidation

Robert Godin, Takashi Hisatomi, Kazunari Domen, James R Durrant
A persistent challenge for the widespread deployment of solar fuels is the development of high efficiency photocatalysts combined with a low-cost preparation and implementation route. Since its discovery in 2005, GaN:ZnO solid solution has been a benchmark overall water splitting photocatalyst. Notably, GaN:ZnO functionalised with an appropriate proton reduction cocatalyst is one of the few particulate photocatalyst systems that can generate hydrogen and oxygen directly from water using visible light. However, the reasons underlying the remarkable visible light activity of GaN:ZnO are not well understood and photophysical studies of GaN:ZnO have been limited to date...
October 14, 2018: Chemical Science
M V López-Ramón, J Rivera-Utrilla, M Sánchez-Polo, A M S Polo, Antonio J Mota, F Orellana-García, M A Álvarez
In this study, a nickel organic xerogel (X-Ni) was used as semiconductor photocatalyst for the degradation of the herbicide diuron (DRN) in aqueous solution. The main objective of this work was to analyze and compare the effectiveness of solar irradiation to remove DRN from water both by direct photolysis and photocatalytic degradation. We examined the influence of the initial concentration of the herbicide, the solution pH, the presence of different ions in the medium, the chemical composition of the water, and the presence of a photocatalyst, after 240 min of irradiation...
February 10, 2019: Science of the Total Environment
Aliaksandr Kushniarou, Isabel Garrido, José Fenoll, Nuria Vela, Pilar Flores, Ginés Navarro, Pilar Hellín, Simón Navarro
This study aims to demonstrate a technically feasible alternative to remove pesticide residues from agro-waste water produced in farms from remnants in containers and treatment tanks, rinse in tanks after treatments, and cleaning of machines and equipment. For this, the photocatalyzed degradation of 12 pesticides commonly used on vegetables, vines, citrus and fruit crops was investigated in aqueous suspensions of TiO2 in tandem with Na2 S2 O8 at pilot plant scale under natural sunlight in Murcia (SE of Spain) during summer and winter seasons...
October 4, 2018: Chemosphere
Shiman He, Yuying Meng, Qili Wu, Jingling Yang, Senchuan Huang, Xiaohui Li, Shengfu Tong, Tewodros Asefa, Mingmei Wu
Owing to its excellent chemical stability and low cost, titanium dioxide (TiO2) has been widely studied as a photoanode for photoelectrochemical (PEC) water splitting. However, TiO2's practical applications in solar energy-to-synthetic fuel conversion processes have been constrained by its inherently poor ability to transport photogenerated electrons and holes. In this paper, we report Ta-doped porous TiO2 nanorod arrays on Ta foil (Ta-PTNA) that do not possess this issue and that can thus efficiently photoelectrocatalyze water oxidation, helping the production of H2 (a clean fuel) from water at the expense of solar light...
October 11, 2018: Nanoscale
Yejun Xiao, Yu Qi, Xiuli Wang, Xiaoyu Wang, Fuxiang Zhang, Can Li
The development of new metal-organic frameworks (MOFs) with dual functions of both water reduction and oxidation under visible-light irradiation is highly desirable for promising solar water splitting, but is not yet reported. Herein, a cadmium-based MOF (denoted as "Cd-TBAPy") single crystal with a 2D layered framework by employing 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4 TBAPy) as an organic linker is reported, which exhibits good visible-light absorption with edge of ≈600 nm. The Mott-Schottky (M-S) measurement and UV-vis analysis integrally reveal that the Cd-TBAPy is an n-type semiconductor with a bandgap of ≈2...
September 17, 2018: Advanced Materials
Yanyan Zhao, Xingxu Yan, Ke R Yang, Sufeng Cao, Qi Dong, James E Thorne, Kelly L Materna, Shasha Zhu, Xiaoqing Pan, Maria Flytzani-Stephanopoulos, Gary W Brudvig, Victor S Batista, Dunwei Wang
Heterogeneous catalysts with atomically defined active centers hold great promise for high-performance applications. Among them, catalysts featuring active moieties with more than one metal atom are important for chemical reactions that require synergistic effects but are rarer than single atom catalysts (SACs). The difficulty in synthesizing such catalysts has been a key challenge. Recent progress in preparing dinuclear heterogeneous catalysts (DHCs) from homogeneous molecular precursors has provided an effective route to address this challenge...
September 26, 2018: ACS Central Science
Yen-Ching Lin, Sri Chandana Panchangam, Li-Chun Liu, Angela Yu-Chen Lin
Photolysis is considered one of the most important mechanisms for the degradation of pharmaceuticals. Photodecomposition processes to remove pharmaceuticals in water treatment presently use artificial UV light incorporated in advanced oxidation processes. However, UV lighting devices consume a substantial amount of energy and have high operational costs. To develop low energy treatment systems and make good use of abundant sunlight, a natural energy resource as a green technology is needed. As such, a system that combines sunlight focusing, solar tracking and continuous reaction was designed and constructed in the present study, and its application potential as a pharmaceutical water treatment option was tested...
September 21, 2018: Chemosphere
Tayyebeh Soltani, Ahmad Tayyebi, Byeong-Kyu Lee
Among the various synthetic techniques, the sonochemical method has emerged as an interesting method for fabricating different photocatalysis materials with unique photoelectrochemical (PEC) properties. In comparison with the classical method without sonication, this study examines the promoting effect of ultrasonic irradiation during the synthesis of tungsten oxide (WO3 ) nanoplates within short reaction times (15 and 30 min). The shorter ultrasonic reaction time (15 min) was sufficient for the uniform growth of thin and compact layers of WO3 nanoparticles (NPs) on the surface of a tungsten foil...
September 25, 2018: Ultrasonics Sonochemistry
Meilan Pan, Zhihao Chen, Chao Shan, Yanfeng Wang, Bingcai Pan, Guandao Gao
Sulfate ions (SO4 2- ) are ubiquitous in aqueous environments and are generally considered to be inert due to their chemical stability. For the first time, we found that SO4 2- can be activated into SO4 2- -type radicals (e.g., SO3 - , SO5 - , SO4 - ) in the presence of phenolic compounds under simulated or natural solar irradiation. In turn, the radicals promoted the transformation and mineralization of phenolic compounds compared to that in the absence of SO4 2- with reaction rate constants ranging from 0...
September 24, 2018: Chemosphere
Kiwon Kim, Jun Hyuk Moon
A photoanode capable of high-efficiency water oxidation at low bias potential is essential for its practical application for photocathode-coupled tandem systems. To address this issue, a photoanode with low turn-on voltage for water oxidation and high charge separation efficiency at low bias potential is essential. In this study, we demonstrate the photoanode of the BiVO4 /ZnO three-dimensional (3D) bicontinuous (BC) structure. ZnO has a relatively cathodic flat-band potential, which leads to low turn-on potential; the BiVO4 /ZnO 3D BC photoanode shows an onset potential of 0...
October 10, 2018: ACS Applied Materials & Interfaces
Shi-Fang Duan, Zhen-Xing Zhang, Yuan-Yuan Geng, Xiao-Qiang Yao, Miao Kan, Yi-Xin Zhao, Xiao-Bo Pan, Xiong-Wu Kang, Chun-Lan Tao, Dong-Dong Qin
Developing high surface area nanostructured electrodes with fast charge separation is one of the main challenges for exploring cupric oxide (CuO)-based photocathodes in solar-driven hydrogen production applications. Herein, brand new 1D branched CuO nanowire arrays have been achieved on fluorine-doped tin oxide-coated glass (FTO) through a two-step wet chemical redox reaction. X-ray diffraction patterns, Raman spectra and X-ray photoelectron spectroscopy confirm the pure phase characteristic of the resulting branched CuO...
September 27, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Zhishan Luo, Yidong Hou, Jinshui Zhang, Sibo Wang, Xinchen Wang
The development of efficient, robust and earth-abundant catalysts for photocatalytic conversions has been the Achilles' heel of solar energy utilization. Here, we report on a chemical approach based on ligand designed architectures to fabricate unique structural molecular catalysts coupled with appropriate light harvesters (e.g., carbon nitride and Ru(bpy)3 2+ ) for photoredox reactions. The "Co4 O4 " cubane complex Co4 O4 (CO2 Me)4 (RNC5 H4 )4 (R = CN, Br, H, Me, OMe), serves as a molecular catalyst for the efficient and stable photocatalytic water oxidation and CO2 reduction...
2018: Beilstein Journal of Organic Chemistry
Paulina Wach, Grzegorz Spólnik, Krzysztof J Rudziński, Krzysztof Skotak, Magda Claeys, Witold Danikiewicz, Rafał Szmigielski
In-cloud processing of volatile organic compounds is one of the significant routes leading to secondary organic aerosol (SOA) in the lower troposphere. In this study, we demonstrate that two atmospherically relevant α,β-unsaturated carbonyls, i.e., but-3-en-2-on (methyl vinyl ketone, MVK) and 2-methylopropenal (methacrolein, MACR), undergo sulfate radical-induced transformations in dilute aqueous systems under photochemical conditions to form organosulfates previously identified in ambient aerosols and SOA generated in smog chambers...
September 7, 2018: Chemosphere
Peng Zhang, Le Yu, Xiong Wen David Lou
Designing advanced structures for heterojunction photocatalysts is an effective approach to enhance their performance toward solar-energy conversion. Herein we develop a facile synthetic strategy for the fabrication of Fe2 O3 -TiO2 microdumbbells. With the assistance of preferentially adsorbed hexadecylamine molecules, amorphous TiO2 nanospheres with tunable size are grown at the two ends of Fe-based metal-organic compound microrods. Subsequent annealing of the hybrid obtained leads to the formation of a novel heterostructured Fe2 O3 -TiO2 microdumbbell photocatalyst...
September 24, 2018: Angewandte Chemie
Mengyuan Zhang, Rajini P Antony, Sing Yang Chiam, Fatwa Firdaus Abdi, Lydia Helena Wong
Solar water oxidation is considered as one of the most promising methods to utilize solar energy efficiently, and bismuth vanadate (BiVO4) is a potential photoanode. Catalyst loading on BiVO4 is often used to tackle the limitations of charge recombination and sluggish kinetics. In this study, amorphous nickel oxide (NiOx) is loaded on BiVO4 by photochemical metal organic deposition method. The resulting NiOx/Mo:BiVO4 photoanodes demonstrates a 2-fold improvement of photocurrent density of 2.44 mA cm-2 at 1...
September 24, 2018: ChemSusChem
Lodvert Tchibota Poaty, Kanchan Ulman, Nicola Seriani, Bernard M'Passi-Mabiala, Ralph Gebauer
We use density functional theory-based calculations to study structural, electronic, and magnetic properties of two key reaction intermediates on a hematite, [Formula: see text]-Fe2 O3 , photoanode during the solar-driven water splitting reaction. Both intermediates contain an oxygen atom bonded to a surface iron atom. In one case, the adsorbed oxygen also forms a peroxo bond with a lattice oxygen from hematite; in the second case no such bond is formed. Both configurations are energetically equivalent and are related to the overpotential-determining step in the oxygen evolution reaction...
September 18, 2018: Journal of Molecular Modeling
Sebastiano Bellani, Maria Rosa Antognazza, Francesco Bonaccorso
Hydrogen is considered a promising environmentally friendly energy carrier for replacing traditional fossil fuels. In this context, photoelectrochemical cells effectively convert solar energy directly to H2 fuel by water photoelectrolysis, thereby monolitically combining the functions of both light harvesting and electrolysis. In such devices, photocathodes and photoanodes carry out the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER), respectively. Here, the focus is on photocathodes for HER, traditionally based on metal oxides, III-V group and II-VI group semiconductors, silicon, and copper-based chalcogenides as photoactive material...
September 16, 2018: Advanced Materials
Junyan Cui, Can Li, Fuxiang Zhang
The rapid fossil-fuel consumption, severe environmental concerns, and growing energy demands call for the exploitation of environmentally friendly, recyclable new energy. Fuel-producing artificial system that directly converts solar energy into fuels by mimicking natural photosynthesis, is expected to achieve this goal. Among them, the conversion of solar energy to hydrogen energy through photocatalytic water splitting process over a particulate semiconductor is one of the most promising routes due to the advantages such as simplicity, cheapness and ease for large-scale production etc...
September 13, 2018: ChemSusChem
Min Wang, Hongtao Yu, Xiaoqian Ma, Yao Yao, Liang Wang, Lihui Liu, Kun Cao, Shuli Liu, Chen Dong, Baomin Zhao, Chunyuan Song, Shufen Chen, Wei Huang
Graphene is an ideal substitute for indium tin oxide electrode in organic photovoltaic (OPV) devices, due to its outstanding electrical, optical, chemical and mechanical properties. However, the graphene electrode suffers from work function mismatch with common hole injection layer and intrinsic hydrophobic property. Here, Cux O is proposed to modify monolayer graphene in order to increase the work function of graphene (from 4.45 to 4.76 eV) and decrease the water contact angle (from 88° to 59°). Then, the OPV devices based on the Cux O modified graphene anode are fabricated successfully, and power conversion efficiency (PCE) is enhanced from 4...
September 3, 2018: Optics Express
Yiming Bai, Bo Yang, Xiaohan Chen, Fuzhi Wang, Tasawar Hayat, Ahmed Alsaedi, Zhan'ao Tan
Rationally controlling the vertical component distribution within a photoactive layer is crucial for efficient polymer solar cells (PSCs). Herein, fine-tuning the surface free energy (SFE) of the titanium(IV) oxide bis(2,4-pentanedionate) (TOPD) cathode buffer layer is proposed to achieve a desired perpendicular component distribution for the PBDB-T:ITIC-M photoactive layer. The Owens-Wendt method is adopted to precisely calculate the SFE of TOPD film jointly based on the water contact angle and the diiodomethane contact angle...
2018: Frontiers in Chemistry
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"