A quantitative assessment of the competition between water and anion oxidation at WO_3 photoanodes in acidic aqueous electrolytes
Abstract
The faradaic efficiency for O_2(g) evolution at thin-film WO_3 photoanodes has been evaluated in a series of acidic aqueous electrolytes. In 1.0 M H_2SO_4, persulfate was the predominant photoelectrochemical oxidation product, and no O_2 was detected unless catalytic quantities of Ag^+(aq) were added to the electrolyte. In contact with 1.0 M HClO_4, dissolved O_2 was observed with nearly unity faradaic efficiency, but addition of a hole scavenger, 4-cyanopyridine N-oxide, completely suppressed O_2 formation. In 1.0 M HCl, Cl_2(g) was the primary oxidation product. These results indicate that at WO_3 photoanodes, water oxidation is dominated by oxidation of the acid anions in 1.0 M HCl, H_2SO_4, and HClO_4, respectively.
Additional Information
© 2012 The Royal Society of Chemistry. Received 19th October 2011, Accepted 7th December 2011. First published on the web 03 Jan 2012. We acknowledge the National Science Foundation (NSF) Powering the Planet Center for Chemical Innovation (CCI-Solar), Grants CHE-0802907 and CHE-0947829, and the Molecular Materials Research Center of the Beckman Institute at the California Institute of Technology, for support. QM also acknowledges the NSF for support as a CCI-Solar Postdoctoral Fellow.Attached Files
Published - Mi2012p17291Energ_Environ_Sci.pdf
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Additional details
- Eprint ID
- 29496
- Resolver ID
- CaltechAUTHORS:20120228-074506627
- CHE-0802907
- NSF
- CHE-0947829
- NSF
- Caltech Beckman Institute
- NSF Postdoctoral Fellowship
- Created
-
2012-02-28Created from EPrint's datestamp field
- Updated
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2021-11-09Created from EPrint's last_modified field
- Caltech groups
- CCI Solar Fuels