Initial Phase of Photoelectrochemical Conditioning of Silicon in Alkaline Media: Surface Chemistry and Topography
Abstract
Oxidation and dissolution phenomena of Si(111) in alkaline electrolyte are investigated by a combination of photoelectrochemistry, scanning probe microscopy (SPM), transmission electron microscopy (TEM) and in-system synchrotron radiation photoelectron spectroscopy (SRPES). The surface topography in the initial anodic potential regime shows the formation of mesoscale pores with widths in the range 300–500 nm and partial surface oxidation. The surface chemistry assessment by SRPES shows patchy silicon oxide growth, suboxides, and remnants of the former hydrogen terminated surface areas. The use of the obtained self-organized nanostructures for application in nanoemitter photocatalytic solar cells is discussed. The necessary requirements regarding the total surface area of electrocatalysts needed to sustain the current density due to light-induced excess minority carriers in conjunction with the exchange current density of the considered heterogeneous catalysts is discussed.
Additional Information
© 2013 American Chemical Society. Received: February 22, 2013; Revised: July 7, 2013; Published: July 16, 2013. This material is based upon work performed by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, as follows: Part of the electrochemical experiments were supported though the Office of Science of the U.S. Department of Energy under Award No. DE-SC0004993; the SRPES and ERDA measurements and the AFM and TEM images were supported by the Deutsche Forschungsgemeinschaft-DFG under Award No. LE 1192/4-1/2. The authors are grateful to M. Kanis and H. Jungblut for contributing to the SRPES experiments, to M. Aggour for his help regarding electrochemical measurements, to U. Bloeck for recording of the TEM images, and to F. Munnik and K. Saravanan for performing the ERDA measurements. M.L. is grateful for financial support of the DFG (Award No. LE 1192/4-1/2).Additional details
- Eprint ID
- 41137
- Resolver ID
- CaltechAUTHORS:20130906-091022940
- DE-SC0004993
- Department of Energy (DOE)
- LE 1192/4-1/2
- Deutsche Forschungsgemeinschaft (DFG)
- Created
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2013-09-16Created from EPrint's datestamp field
- Updated
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2021-11-10Created from EPrint's last_modified field
- Caltech groups
- JCAP