The Self-Passivation Mechanism in Degradation of BiVO₄ Photoanode.

ABSTRACT: BiVO₄ is a promising photoanode material for solar-assisted water splitting in a photoelectrochemical cell but has a propensity to degrade. Investigations carried out here in 0.1 M Na₂SO₄ electrolyte showed that degradation is by dissolution of V in the electrolyte while Bi is retained on the anode probably in the form of solid Bi oxide (Bi₂O₃, Bi₄O₇). Accumulation of Bi oxide on the anode surface leads to passivation from further degradation. Thermodynamic modeling of possible degradation reactions has provided theoretical support to this mechanism. This self-passivation is accompanied by a decrease in photocurrent density, but it protects the anode against extensive photocorrosion and contributes to long-term st

SUBMITTER: Yao X 

PROVIDER: S-EPMC6744392 | biostudies-literature | 2019 Sep

REPOSITORIES: biostudies-literature