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Different Photostability of BiVO4 in Near-pH-Neutral Electrolytes.

ABSTRACT: Photoelectrochemical water splitting is a promising route to produce hydrogen from solar energy. However, corrosion of photoelectrodes remains a fundamental challenge for their implementation. Here, we reveal different dissolution behaviors of BiVO4 photoanode in pH-buffered borate, phosphate, and citrate (hole-scavenger) electrolytes, studied in operando employing an illuminated scanning flow cell. We demonstrate that decrease in photocurrents alone does not reflect the degradation of photoelectrodes. Changes in dissolution rates correlate to the evolution of surface chemistry and morphology. The correlative measurements on both sides of the liquid-semiconductor junction provide quantitative comparison and mechanistic insights into the degradation processes.

SUBMITTER: Zhang S

PROVIDER: S-EPMC7592387 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Different Photostability of BiVO4 in Near-pH-Neutral Electrolytes.

Zhang Siyuan S Ahmet Ibbi I Kim Se-Ho SH Kasian Olga O Mingers Andrea M AM Schnell Patrick P Kölbach Moritz M Lim Joohyun J Fischer Anna A Mayrhofer Karl J J KJJ Cherevko Serhiy S Gault Baptiste B van de Krol Roel R Scheu Christina C

ACS applied energy materials 20201006 10

Photoelectrochemical water splitting is a promising route to produce hydrogen from solar energy. However, corrosion of photoelectrodes remains a fundamental challenge for their implementation. Here, we reveal different dissolution behaviors of BiVO4 photoanode in pH-buffered borate, phosphate, and citrate (hole-scavenger) electrolytes, studied in operando employing an illuminated scanning flow cell. We demonstrate that decrease in photocurrents alone does not reflect the degrad ...[more]

PMID: 33134878

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