Photocatalytic Water Oxidation with Nonsensitized IrO2 Nanocrystals under Visible and UV Light
- 27 April 2011
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of the American Chemical Society
- Vol. 133 (19) , 7264-7267
- https://doi.org/10.1021/ja200144w
Abstract
Rutile IrO2 is known as being among the best electrocatalysts for water oxidation. Here we report on the unexpected photocatalytic water oxidation activity of 1.98 nm ± 0.11 nm succinic acid-stabilized IrO2 nanocrystals. From aqueous persulfate and silver nitrate solution the nonsensitized particles evolve oxygen with initial rates up to 0.96 μmol min–1, and with a quantum efficiency of at least 0.19% (measured at 530 nm). The catalytic process is driven by visible excitations from the Ir-d(t2g) to the Ir-d(eg) band (1.5–2.75 eV) and by ultraviolet excitations from the O-p band to the Ir-d(eg) (>3.0 eV) band. The formation of the photogenerated charge carriers can be directly observed with surface photovoltage spectroscopy. The results shed new light on the role of IrO2 in dye- and semiconductor-sensitized water splitting systems.Keywords
This publication has 25 references indexed in Scilit:
- Efficient Electro-Oxidation of Water near Its Reversible Potential by a Mesoporous IrOx Nanoparticle FilmThe Journal of Physical Chemistry C, 2009
- Photoassisted Overall Water Splitting in a Visible Light-Absorbing Dye-Sensitized Photoelectrochemical CellJournal of the American Chemical Society, 2009
- A Novel Photodeposition Method in the Presence of Nitrate Ions for Loading of an Iridium Oxide Cocatalyst for Water SplittingChemistry Letters, 2005
- Remarkably high activity of electrodeposited IrO2 film for electrocatalytic water oxidationJournal of Electroanalytical Chemistry, 2005
- Oxysulfide Sm2Ti2S2O5 as a Stable Photocatalyst for Water Oxidation and Reduction under Visible Light Irradiation (λ ≤ 650 nm)Journal of the American Chemical Society, 2002
- A High-Throughput Optical Screening Method for the Optimization of Colloidal Water Oxidation CatalystsJournal of the American Chemical Society, 2002
- Photoreactions on LaTiO2N under Visible Light IrradiationThe Journal of Physical Chemistry A, 2002
- Comparative study of new and established heterogeneous oxygen catalystsJournal of the Chemical Society, Faraday Transactions, 1991
- Metal oxides as heterogeneous catalysts for oxygen evolution under photochemical conditionsJournal of the Chemical Society, Faraday Transactions 1: Physical Chemistry in Condensed Phases, 1988
- Anodic Evolution of Oxygen on Sputtered Iridium Oxide FilmsJournal of the Electrochemical Society, 1981