Abstract
BiVO4 has been formed into heterojunctions with other metal oxide semiconductors to increase the efficiency for solar water oxidation. Here, we suggest that heterojunction photoanodes of Si and BiVO4 can also increase the efficiency of charge separation and reduce the onset potential of the photocurrent by utilizing the high conduction band edge potential of Si in a dual-absorber system. We found that a thin TiO2 interlayer is required in this structure to realize the suggested photocurrent density enhancement and shifts in onset potential. Si/TiO2/BiVO4 photoanodes showed 1.0 mA/cm2 at 1.23 V versus the reversible hydrogen electrode (RHE) with 0.11 V (vs RHE) of onset potential, which were a 3.3-fold photocurrent density enhancement and a negative shift in onset potential of 300 mV compared to the performance of FTO/BiVO4 photoanodes. (Graph Presented).
Original language | English |
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Pages (from-to) | 5788-5796 |
Number of pages | 9 |
Journal | ACS Applied Materials and Interfaces |
Volume | 7 |
Issue number | 10 |
DOIs | |
Publication status | Published - 2015 Mar 18 |
Bibliographical note
Publisher Copyright:© 2015 American Chemical Society.
Keywords
- BiVO
- Si
- TiO
- dual absorber
- heterojunction
- onset potential
ASJC Scopus subject areas
- General Materials Science