Robust dihydroxyacetone production via photoelectrochemical glycerol oxidation using an oxygen vacant BiVO4 photoanode

Abstract

Photoelectrochemical conversion of glycerol into high-value dihydroxyacetone offers a sustainable approach via BiVO4 semiconductor materials, which manifest highly photoactive properties. However, dihydroxyacetone production poses a limitation due to poor charge transport ability and fast electron–hole recombination of BiVO4. Herein, we fabricated N2-annealed BiVO4 through a facile spin-coating method and an N2 annealing process. The effect of N2 treatment did not significantly impact the surficial catalytic efficiency, while the bulk efficiency was increased, resulting from changes in oxygen vacancy concentration and carrier density. Owing to improvement in bulk electron–hole separation efficiency, N2-annealed BiVO4 at 150 °C exhibited an enhanced photoelectrochemical dihydroxyacetone production rate of 160 mmol m−2 h−1 at 1.0 V vs. RHE, which was more than 2 times higher than that of pristine BiVO4. This work establishes a pathway for optimizing semiconductor engineering via post-annealing treatment and provides a modification strategy of BiVO4 for achieving advanced production of dihydroxyacetone.