Solar-driven H2O2 production via cooperative auto- and photocatalytic oxidation in fine-tuned reaction media

Abstract

Solar photocatalysis has emerged as a sustainable route to produce H2O2; however, the structural design of photocatalysts makes them expensive, limiting their practical applications. Inspired by the industrial anthraquinone process, we developed a new reaction design for solar H2O2 production using an organic working solution (OWS) comprising aryl alcohols and a metal-free polymeric photocatalyst. The synergistic auto- and photocatalytic oxidation of aryl alcohols in the OWS allowed for the quantitative generation of H2O2 by counter O2 reduction. The fine modulation of the OWS with water enhanced the photocatalytic route, resulting in an unprecedented H2O2 production rate of 46.9 mmol h？1 g？1 with a solar-to-chemical conversion efficiency of 1.1% under simulated sunlight. Pure H2O2 was obtained after extraction and purification by membrane filtration, and was directly used in large-scale water purification as a proof of concept. This study demonstrates the importance of reaction design in photocatalytic applications and will promote future advancements in green, solar-driven H2O2 production.