Enhancing Catalytic Activity by Narrowing Local Energy Gaps-X-Ray Studies of a Manganese Water Oxidation Catalyst

Colloidal solutions of iridium oxide hydrate (IrO2·nH2O) were formed using porphyrin stabilizers bearing malonate-like functional groups at each of the four meso positions of the porphyrin ring. Cyclic voltammetry and monitoring of solution oxygen concentrations under constant applied potential demonstrated the electrochemical catalytic activity of the porphyrin–IrO2·nH2O complexes for the oxidation of water to oxygen. Quenching of the porphyrin fluorescence in the complex implies strong interaction between the porphyrin and the IrO2·nH2O. These results mark a step toward developing a porphyrin-based photoanode for use in a photoelectrochemical water-splitting cell.

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Electronic Structure Assessment: Combined Density Functional Theory Calculations and Ru L2,3-Edge X-ray Absorption Near-Edge Spectroscopy of Water Oxidation Catalyst

The Journal of Physical Chemistry C ◽

10.1021/jp405648h ◽

2013 ◽

Vol 117 (37) ◽

pp. 18994-19001 ◽

Cited By ~ 4

Author(s):

Igor Alperovich ◽

Dooshaye Moonshiram ◽

Javier J. Concepcion ◽

Yulia Pushkar

Keyword(s):

Density Functional Theory ◽

Electronic Structure ◽

Water Oxidation ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Oxidation Catalyst ◽

Functional Theory ◽

X Ray ◽

Structure Assessment ◽

X Ray Absorption

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A facile method for the synthesis of a porous cobalt oxide–carbon hybrid as a highly efficient water oxidation catalyst

Journal of Materials Chemistry A ◽

10.1039/c5ta07813j ◽

2016 ◽

Vol 4 (5) ◽

pp. 1819-1827 ◽

Cited By ~ 38

Author(s):

Mei Zhang ◽

Yong-Liang Huang ◽

Jia-Wei Wang ◽

Tong-Bu Lu

Keyword(s):

Catalytic Activity ◽

Cobalt Oxide ◽

Water Oxidation ◽

Oxidation Catalyst ◽

Highly Efficient

A cobalt oxide–carbon hybrid was synthesized, which exhibited outstanding chemical, photochemical and electrochemical water oxidation catalytic activity.

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The Mn 4 Ca photosynthetic water-oxidation catalyst studied by simultaneous X-ray spectroscopy and crystallography using an X-ray free-electron laser

Philosophical Transactions of the Royal Society B Biological Sciences ◽

10.1098/rstb.2013.0324 ◽

2014 ◽

Vol 369 (1647) ◽

pp. 20130324 ◽

Cited By ~ 14

Author(s):

Rosalie Tran ◽

Jan Kern ◽

Johan Hattne ◽

Sergey Koroidov ◽

Julia Hellmich ◽

...

Keyword(s):

Free Electron ◽

Water Oxidation ◽

Free Electron Laser ◽

Room Temperature ◽

Oxidation Catalyst ◽

Cryogenic Temperatures ◽

New Approach ◽

X Ray ◽

The Past ◽

Photosynthetic Water Oxidation

The structure of photosystem II and the catalytic intermediate states of the Mn 4 CaO 5 cluster involved in water oxidation have been studied intensively over the past several years. An understanding of the sequential chemistry of light absorption and the mechanism of water oxidation, however, requires a new approach beyond the conventional steady-state crystallography and X-ray spectroscopy at cryogenic temperatures. In this report, we present the preliminary progress using an X-ray free-electron laser to determine simultaneously the light-induced protein dynamics via crystallography and the local chemistry that occurs at the catalytic centre using X-ray spectroscopy under functional conditions at room temperature.

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