A biomimetic all-inorganic photocatalyst for the artificial photosynthesis of hydrogen peroxide

Abstract

The artificial photosynthesis of H₂O₂ from water and O₂ presents a sustainable route for its production. Remarkable progress in the rate of reaction has recently been achieved mainly by using semiconducting organic polymer photocatalysts. In view of the use under harsh oxidative conditions, the development of robust inorganic photocatalysts is highly desired. Here we present a photocatalyst with the unit consisting of a single Au particle and an interconnected cluster of SnO₂ nanocrystals with the surface modified with SbCl₃ (Au@SnO₂–Sb(III)). Under visible-light irradiation (λ_ex = 420 nm), Au@SnO₂–Sb(III) stably produces H₂O₂ with a rate of 6.1 mM g⁻¹ h⁻¹ and an external quantum yield of 1.1%. This striking photocatalytic activity of Au@SnO₂–Sb(III) originates from the action of SnO₂–Sb(III) as a “light antenna” and “electron transporter”, the electrocatalytic activity of Au NPs for the two electron-oxygen reduction reaction, the visible-light induced activity of SnO₂–Sb(III) for the oxygen evolution reaction, the weak adsorptivity for H₂O₂, and the robustness.