Au Nanoparticles Supported on BiVO 4 : Effective Inorganic Photocatalysts for H 2 O 2 Production from Water and O 2 under Visible Light

The design of a safe and sustainable process for the synthesis of hydrogen peroxide (H 2 O 2 ) is a very important subject from the viewpoint of green chemistry. Photocatalytic H 2 O 2 production with earth-abundant water and molecular oxygen (O 2 ) as resources is an ideal process. A successful system based on an organic semiconductor has been proposed; however, it suffers from poor photostability. Here we report an inorganic photocatalyst for H 2 O 2 synthesis. Visible light irradiation (λ >420 nm) of the semiconductor BiVO 4 loaded with Au nanoparticles (Au/BiVO 4 ) in pure water with O 2 successfully produces H 2 O 2 . The bottom of the BiVO 4 conduction band (0.02 V vs NHE, pH 0) is more positive than the one-electron reduction potential of O 2 (−0.13 V) while more negative than the two-electron reduction potential of O 2 (0.68 V). This thus suppresses one-electron reduction of O 2 and selectively promotes two-electron reduction of O 2, resulting in efficient H 2 O 2 formation.