Abstract
Planar and three-dimensionally structured p-Si devices, consisting of an electrodeposited Co-P catalyst on arrays of Si microwires or Si micropyramids, were used as photocathodes for solar-driven hydrogen evolution in 0.50 M H2SO4(aq) to assess the effects of electrode structuring on parasitic absorption by the catalyst. Without the use of an emitter layer, p-Si/Co-P microwire arrays produced a photocurrent density of -10 mA cm-2 at potentials that were 130 mV more positive than those of optimized planar p-Si/Co-P devices. Champion p-Si/Co-P microwire array devices exhibited ideal regenerative cell solar-to-hydrogen efficiencies of >2.5% and were primarily limited by the photovoltage of the p-Si/Co-P junction. The vertical sidewalls of the Si microwire photoelectrodes thus minimized effects due to parasitic absorption at high loadings of catalyst for device structures with or without emitters.
Original language | English |
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Pages (from-to) | 612-617 |
Number of pages | 6 |
Journal | ACS Energy Letters |
Volume | 3 |
Issue number | 3 |
DOIs | |
Publication status | Published - Mar 9 2018 |
ASJC Scopus subject areas
- Chemistry (miscellaneous)
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Energy Engineering and Power Technology
- Materials Chemistry