Recently, a new method to effectively engineer the bandgap of barium bismuth niobate (BBNO) double perovskite was reported. However, the planar electrodes based on BBNO thin films show low photocurrent densities for water oxidation owing to their poor electrical conductivity. Here, it is reported that the photoelectrochemical (PEC) activity of BBNO‐based electrodes can be dramatically enhanced by coating thin BBNO layers on tungsten oxide (WO3) nanosheets to solve the poor conductivity issue while maintaining strong light absorption. The PEC activity of BBNO/WO3nanosheet photoanodes can be further enhanced by applying Co0.8Mn0.2O
- Award ID(s):
- 1654780
- NSF-PAR ID:
- 10200078
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 12
- Issue:
- 5
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 3121 to 3128
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract x nanoparticles as a co‐catalyst. A photocurrent density of 6.02 mA cm−2at 1.23 V (vs reversible hydrogen electrode (RHE)) is obtained using three optically stacked, but electrically parallel, BBNO/WO3nanosheet photoanodes. The BBNO/WO3nanosheet photoanodes also exhibit excellent stability in a high‐pH alkaline solution; the photoanodes demonstrate negligible photocurrent density decay while under continuous PEC operation for more than 7 h. This work suggests a viable approach to improve the PEC performance of BBNO absorber‐based devices. -
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