Photoelectrochemical OER activity by employing BiVO with manganese oxide co-catalysts

• Published in: Physical chemistry chemical physics : PCCP Vol. 22; no. 2; pp. 811 - 817
• Main Authors: Kaur, Manjodh, Chhetri, Manjeet, Rao, C. N. R
• Format: Journal Article
• Published: 02.01.2020
• ISSN: 1463-9076; 1463-9084
• DOI: 10.1039/c9cp05293c

The structure-activity relationship in the electrochemical OER has been studied widely, but aspects of the photoelectrochemical (PEC) O 2 evolution activity with different manganese oxides are not fully explored. In the present study different manganese oxides (MnO 2 , MnO x (a mixture of Mn 3+ and Mn 4+ ions), Mn 2 O 3 , and Mn 3 O 4 ) have been electrodeposited onto the BiVO 4 photoanode as co-catalysts for PEC water splitting. We find that BiVO 4 -MnO x shows the lowest onset potential of 0.33 V vs. RHE and the highest activity among the manganese oxides. Annealing at different temperatures results in the improvement of the OER kinetics at the interface with some detrimental effect on the activity of BiVO 4 . Such a study may lead to useful changes in the fabrication of semiconductor thin film photoelectrodes useful for PEC water splitting. Inspired by natural photosynthesis, various manganese oxides have been studied as co-catalysts with BiVO 4 for photoelectrochemical water splitting.