Enhanced Carrier Transport and Bandgap Reduction in Sulfur-Modified BiVO4 Photoanodes

Marlene Lamers, Wenjie Li, Marco Favaro, David E. Starr, Dennis Friedrich, Sheikha F. Lardhi, Luigi Cavallo, Moussab Harb, Roel van de Krol, Lydia H. Wong, Fatwa F. Abdi

Research output: Contribution to journalArticlepeer-review

19 Scopus citations

Abstract

Recent progress on bismuth vanadate (BiVO) has shown it to be among the highest performing metal oxide photoanode materials. However, further improvement, especially in the form of thin film photoelectrodes, is hampered by its poor charge carrier transport and its relatively wide bandgap. Here, sulfur incorporation is used to address these limitations. A maximum bandgap decrease of ∼0.3 eV is obtained, which increases the theoretical maximum solar-to-hydrogen efficiency from 9 to 12%. Hard X-ray photoelectron spectroscopy measurements as well as density functional theory calculations show that the main reason for the bandgap decrease is an upward shift of the valence band maximum. Time-resolved microwave conductivity measurements reveal a ∼3 times higher charge carrier mobility compared to unmodified BiVO, resulting in a ∼70% increase in the carrier diffusion length. This work demonstrates that sulfur incorporation can be a promising and practical method to improve the performance of wide-bandgap metal oxide photoelectrodes.
Original languageEnglish (US)
Pages (from-to)8630-8638
Number of pages9
JournalChemistry of Materials
Volume30
Issue number23
DOIs
StatePublished - Nov 21 2018

Fingerprint

Dive into the research topics of 'Enhanced Carrier Transport and Bandgap Reduction in Sulfur-Modified BiVO4 Photoanodes'. Together they form a unique fingerprint.

Cite this