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08 Jan 23:36

Atomically-thick two-dimensional crystals: electronic structure regulation and energy device construction

Chem. Soc. Rev., 2014, 43,530-546
DOI: 10.1039/C3CS60231A, Tutorial Review
Yongfu Sun, Shan Gao, Yi Xie
Progress and challenges in fine structure characterization, electronic structure regulation and energy device construction of atomically-thick two-dimensional crystals.
The content of this RSS Feed (c) The Royal Society of Chemistry
09 Dec 18:05

Visible light driven photocatalysis mediated via ligand-to-metal charge transfer (LMCT): Alternative way of solar activation of titania

Energy Environ. Sci., 2013, Accepted Manuscript
DOI: 10.1039/C3EE43147A, Minireview
Guan Zhang, Gonu Kim, Wonyong Choi
Visible light harvesting or utilization through semiconductor photocatalysis is a key technology for solar chemical conversion processes. Although titania nanoparticles are popular as a base material of photocatalysis, the lack...
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23 Dec 05:35

Hydrogen Evolution from Neutral Water under Aerobic Conditions Catalyzed by Cobalt Microperoxidase-11

by Jesse G. Kleingardner, Banu Kandemir and Kara L. Bren

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/ja406818h
21 Dec 12:09

Searching for the thermodynamic limit - a DFT study of the step-wise water oxidation of the bipyramidal Cu7 cluster.

by Stenlid JH, Johansson AJ, Brinck T

Searching for the thermodynamic limit - a DFT study of the step-wise water oxidation of the bipyramidal Cu7 cluster.

Phys Chem Chem Phys. 2013 Dec 20;

Authors: Stenlid JH, Johansson AJ, Brinck T

Abstract
Oxidative degradation of copper in aqueous environments is a major concern in areas such as catalysis, electronics and construction engineering. A particular challenge is to systematically investigate the details of this process for non-ideal copper surfaces and particles under the conditions found in most real applications. To this end, we have used hybrid density functional theory to study the oxidation of a Cu7 cluster in water solution. Especially, the role of a large water coverage is explored. This has resulted in the conclusion that, under atmospheric H2 pressures, the thermodynamically most favored state of degradation is achieved upon the generation of four H2 molecules (i.e. Cu7 + 8H2O → Cu7(OH)8 + 4H2) in both condensed and gas phases. This state corresponds to an average oxidation state below Cu(i). The calculations suggest that the oxidation reaction is slow at ambient temperatures with the water dissociation as the rate-limiting step. Our findings are expected to have implication for, among other areas, the copper catalyzed water-gas shift reaction, and for the general understanding of copper corrosion in aqueous environments.

PMID: 24358468 [PubMed - as supplied by publisher]

24 Dec 19:22

Mechanism of the Formation of Carboxylate from Alcohols and Water Catalyzed by a Bipyridine-Based Ruthenium Complex: A Computational Study

by Haixia Li and Michael B. Hall

TOC Graphic

Journal of the American Chemical Society
DOI: 10.1021/ja410541v
20 Dec 11:48

A simple, low-cost CVD route to thin films of BiFeO3 for efficient water photo-oxidation

J. Mater. Chem. A, 2013, Accepted Manuscript
DOI: 10.1039/C3TA14824F, Communication
Savio Moniz, Raul Quesada Cabrera, Christopher S Blackman, JunWang Tang, Paul Southern, Paul Weaver, Claire J Carmalt
A novel method for preparation of BiFeO3 films via a simple solution-based CVD method is reported using for the first time, a single-source heterobimetallic precursor [CpFe(CO)2BiCl2]. BiFeO3 films display ferroelectric...
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20 Dec 18:20

Silicon/Hematite Core/Shell Nanowire Array Decorated with Gold Nanoparticles for Unbiased Solar Water Oxidation

by Xin Wang, Kui-Qing Peng, Ya Hu, Fu-Qiang Zhang, Bo Hu, Li Li, Meng Wang, Xiang-Min Meng and Shuit-Tong Lee

TOC Graphic

Nano Letters
DOI: 10.1021/nl402205f
23 Dec 18:42

Component Analysis of Dyads Designed for Light-Driven Water Oxidation

by Lars Kohler, Nattawut Kaveevivitchai, Ruifa Zong and Randolph P. Thummel

TOC Graphic

Inorganic Chemistry
DOI: 10.1021/ic4022905
11 Dec 05:33

Molecular Water Oxidation Mechanisms Followed by Transition Metals: State of the Art

by Xavier Sala, Somnath Maji, Roger Bofill, Jordi García-Antón, Lluís Escriche and Antoni Llobet

TOC Graphic

Accounts of Chemical Research
DOI: 10.1021/ar400169p
12 Dec 15:50

A Biomimetic Copper Water Oxidation Catalyst with Low Overpotential.

by Zhang T, Wang C, Liu S, Wang JL, Lin W
Related Articles

A Biomimetic Copper Water Oxidation Catalyst with Low Overpotential.

J Am Chem Soc. 2013 Dec 10;

Authors: Zhang T, Wang C, Liu S, Wang JL, Lin W

Abstract
Simply mixing a Cu(II) salt and 6,6'-dihydroxy-2,2'-bipyridine (H2L) in a basic aqueous solution afforded a highly active water oxidation catalyst (WOC). Cyclic voltammetry of the solution at pH = 12-14 shows irreversible catalytic current with an onset potential of ~0.8 V vs. NHE. Catalytic oxygen evolution takes place in controlled potential electrolysis at a relatively low overpotential of 640 mV. Experimental and computational studies suggest that the L ligand participates in electron transfer processes to facilitate the oxidation of the Cu center to lead to an active WOC with low overpotential, akin to the use of the tyrosine radical by Photosystem II to oxidize the CaMn4 center for water oxidation.

PMID: 24325734 [PubMed - as supplied by publisher]

20 Nov 20:20

A Self-Improved Water-Oxidation Catalyst: Is One Site Really Enough?

by Isidoro López, Mehmed Z. Ertem, Somnath Maji, Jordi Benet-Buchholz, Anke Keidel, Uwe Kuhlmann, Peter Hildebrandt, Christopher J. Cramer, Victor S. Batista, Antoni Llobet

Abstract

The homogeneous catalysis of water oxidation by transition-metal complexes has experienced spectacular development over the last five years. Practical energy-conversion schemes, however, require robust catalysts with large turnover frequencies. Herein we introduce a new oxidatively rugged and powerful dinuclear water-oxidation catalyst that is generated by self-assembly from a mononuclear catalyst during the catalytic process. Our kinetic and DFT computational analysis shows that two interconnected catalytic cycles coexist while the mononuclear system is slowly and irreversibly converted into the more stable dinuclear system: an extremely robust water-oxidation catalyst that does not decompose over extended periods of time.

Thumbnail image of graphical abstract

In for the long haul: The transformation of a highly active mononuclear ruthenium–aqua water-oxidation catalyst into a dinuclear complex during oxygen-evolution catalysis led to the coexistence of two different catalytic cycles in solution (see picture; Ru pink, N blue, O red). The dinuclear species was much more robust than its mononuclear counterpart and remained an active catalyst for water oxidation for extended periods of time.

19 Nov 15:42

Environmental friendly Fe substitutive of Ru in water oxidation catalysis

Publication date: 10 January 2014
Source:Catalysis Communications, Volume 44
Author(s): Albert Poater
The present study pretends to unravel by means of DFT calculations how the energy profile change replacing the precious Ru by the nonprecious Fe for the Ru-Hbpp (in,in-{[RuII(trpy)(H2O)]2(μ-bpp)}3+, trpy=2,2′:6′,2″-terpyridine, bpp=bis(2-pyridyl)-3,5-pyrazolate) water oxidation catalyst. This change might remove or at least decrease the potential carcinogenic toxicity due to Ru, however computationally supposes to increase the difficulty of the right assignment of the ground state multiplicity of dinuclear iron complexes when interacting with oxygen. The reaction pathway for Fe-Hbpp arises promising results and now it is a challenge its synthesis.

Graphical abstract

image
11 Nov 20:10

Porous Cobalt Titanate Nanorod: A New Candidate for Visible Light-Driven Photocatalytic Water Oxidation

by Yang Qu, Wei Zhou, Honggang Fu

Abstract

New narrow band gap semiconductor cobalt titanate (CoTiO3) nanorods are fabricated via an ethylene glycol-mediated route and further calcination in air. The glycolate precursors and porous CoTiO3 nanorods are investigated in detail by using SEM, TEM, XRD, thermogravimetric, FTIR, and UV/Vis spectroscopy and N2 adsorption–desorption isotherm. The effect of calcining temperature is also studied, and 700 °C is found to be the optimal calcining temperature used to prepare porous CoTiO3 nanorods with high crystallinity and porosity as well as excellent photocatalytic performance in water oxidation under visible light irradiation. The highest oxygen production yield is up to 64.6 μmol h−1 without co-catalysts. The high photocatalytic activity for oxygen production is ascribed to the following reasons: 1) the large surface area, which favors absorption and offers more active sites, 2) the suitable narrow band gap, which can use more solar energy, and 3) the 1 D structure, which leads to good electron transport.

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Let there be light! Porous cobalt titanate nanorods with a suitable narrow band gap, large surface area, and good crystallinity is found to be an excellent photocatalyst candidate for visible light-driven photocatalytic water oxidation.

31 Oct 17:07

Carboxylate-rich hybrid ligands in Mn(II) complexes as precursors for water oxidation reactions

Dalton Trans., 2013, Accepted Manuscript
DOI: 10.1039/C3DT51666K, Paper
C. R. Raymond Gan, Zhaolin Liu, Shiqiang Bai, Kian Soo Ong, T. S. Andy Hor
A new family of MnII complexes stabilized by carboxylate-rich hybrid ligands have been synthesized, characterized and applied as catalytic precursors for MnO2¬ nanoparticles in water oxidation by (NH4)2Ce(NO3)6.
The content of this RSS Feed (c) The Royal Society of Chemistry
01 Nov 02:27

Visible light driven non-sacrificial water oxidation and dye degradation with silver phosphates: multi-faceted morphology matters

New J. Chem., 2014, 38,1942-1945
DOI: 10.1039/C3NJ01012K, Letter
Arindam Indra, Prashanth W. Menezes, Michael Schwarze, Matthias Driess
Multi-faceted silver phosphate particles show improved photocatalytic activities compared to the irregular shaped particles both for water oxidation and dye degradation.
The content of this RSS Feed (c) The Royal Society of Chemistry
22 Oct 22:59

A super-efficient cobalt catalyst for electrochemical hydrogen production from neutral water with 80 mV overpotential

Energy Environ. Sci., 2013, Accepted Manuscript
DOI: 10.1039/C3EE42194E, Communication
Lin Chen, Mei Wang, Kan Han, Peili Zhang, Frederic Gloaguen, Licheng Sun
This is an Accepted Manuscript, which has been through the RSC Publishing peer review process and has been accepted for publication. Accepted manuscripts are published online shortly after acceptance. This version of the article will be replaced by the fully edited, formatted and proof read Advance Article as soon as this is available.
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26 Sep 14:52

Geometric and Electronic Structure Contributions to Function in Non-heme Iron Enzymes

by Edward I. Solomon, Kenneth M. Light, Lei V. Liu, Martin Srnec and Shaun D. Wong

TOC Graphic

Accounts of Chemical Research
DOI: 10.1021/ar400149m
07 Oct 15:10

Crystallization of Tungsten Trioxide Having Small Mesopores: Highly Efficient Photoanode for Visible-Light-Driven Water Oxidation

by Debraj Chandra, Kenji Saito, Tatsuto Yui, Masayuki Yagi
Thumbnail image of graphical abstract

Small mesopores are more efficient: A mesoprous oxide semiconductor (tungsten trioxide) having small mesopores was crystallized at high temperature (550 °C) by a simple one-step procedure. The highly crystalline mesoporous WO3 has an extremely high surface area which improves the visible-light-driven photoelectrochemical performance of water oxidation (see picture) relative to WO3 having interparticle mesopores.