Visible-Light-Driven Hydrogen Peroxide Synthesis by a Hybrid Photocatalyst Consisting of Bismuth Vanadate and Bis(hexafluoroacetylacetonato)copper(II) Complex
Miwako Teranishi, Takeshi Kunimoto, Shin‐ichi Naya, Hisayoshi Kobayashi, Hiroaki Tada
Abstract
The adsorption of bis(acetylacetonato)Cu(II) on monoclinic scheelite bismuth vanadate forms an O2-bridged dimer complex on the surface resembling hemocyanin in the biosystems (Cu(acac)2/ms-BiVO4). Visible-light irradiation of Cu(acac)2/ms-BiVO4 in ethanol aqueous solution gives rise to a two-electron oxygen reduction reaction, whereas unmodified ms-BiVO4 is entirely inactive. The replacement of Cu(acac)2 by bis(hexafluoroacetylacetonato)Cu(II) drastically enhances the photocatalytic activity to yield H2O2 with an external quantum yield of 0.47% at λex = 470 nm. Electrochemical measurements show high selectivity (∼100%) for the two-electron reduction of O2. The compatibility of the high photocatalytic activity and selectivity can stem from the charge separation enhancement via the interfacial electron transfer from ms-BiVO4 to the surface complex and its O2-enriching effect near the ms-BiVO4 surface and excellent electrocatalysis for two-electron ORR.