Selective and Efficient Gd-Doped BiVO4 Photoanode for Two-Electron Water Oxidation to H2O2
By Baek, Ji Hyun; Gill, Thomas Mark; Abroshan, Hadi; Park, Sangwook; Shi, Xinjian; N
Published in ACS Energy Letters
2019
Abstract
Photoelectrochemical oxidation of water presents a pathway for sustainable production of hydrogen peroxide (H2O2). Two-electron water oxidation toward H2O2, however, competes with the popular four-electron process to form oxygen and one-electron water oxidation to form OH radical. To date, bismuth vanadate (BiVO4) has been shown to exhibit promising selectivity toward H2O2, especially under illumination, but it suffers from high overpotential and notoriously poor stability. Herein, using density functional theory calculations, we predict that doping BiVO4 with optimal concentrations of gadolinium (Gd) not only enhances its activity for H2O2 production but also improves its stability. Experimentally, we demonstrate that intermediate amounts of Gd doping (6