Solar-driven highly selective conversion of glycerol to dihydroxyacetone using surface atom engineered BiVO4 photoanodes

Dihydroxyacetone is the most desired product in glycerol oxidation reaction because of its highest added value and large market demand among all possible oxidation products. However, selectively oxidative secondary hydroxyl groups of glycerol for highly efficient dihydroxyacetone production still poses a challenge. In this study, we engineer the surface of BiVO 4 by introducing bismuth-rich domains and oxygen vacancies (Bi-rich BiVO 4-x ) to systematically modulate the surface adsorption of secondary hydroxyl groups and enhance photo-induced charge separation for photoelectrochemical glycerol oxidation into dihydroxyacetone conversion. As a result, the Bi-rich BiVO 4-x increases the glycerol oxidation photocurrent density of BiVO 4 from 1.42 to 4.26 mA cm −2 at 1.23 V vs. reversible hydrogen electrode under AM 1.5 G illumination, as well as the dihydroxyacetone selectivity from 54.0% to 80.3%, finally achieving a dihydroxyacetone production rate of 361.9 mmol m −2 h −1 that outperforms all reported values. The surface atom customization opens a way to regulate the solar-driven organic transformation pathway toward a carbon chain-balanced product. Photoelectrochemical oxidation of glycerol to produce dihydroxyacetone is limited by its low selectivity. Here, a bismuth vanadate photoanode enriched with a bismuth-rich surface and containing oxygen vacancies was utilized to overcome this dilemma.