Assembling graphene quantum dots on aminophenol-formaldehyde resin towards efficient artificial photocatalytic hydrogen peroxide synthesis

Abstract

Artificial photocatalytic hydrogen peroxide (H₂O₂) production via metal-free catalysts has attracted increasing attention as an alternative strategy to inorganic photocatalysts because of their affordability, high stabilities, and safety. The relatively low photocatalytic efficiency of these catalysts limits their practical application. In this work, graphene quantum dots (GQDs) were successfully loaded on aminophenol-formaldehyde polymer (APF-GQDs) through a straightforward modification method, and can catalyze the water oxidation reaction and oxygen reduction reaction for H₂O₂ generation. With the help of GQDs, APF-GQDs show a stronger light absorption capacity, narrower bandgap for exciton dissociation, and higher separation and transfer efficiency of photogenerated electrons than that of the pristine APF, which contributes to an excellent H₂O₂ synthesis (apparent quantum efficiency, 12.9% at 420 nm and solar-to-chemical conversion efficiency, 1.14%). Our photocatalytic system retains high activity (2361.8–2826.0 μmol g⁻¹) for solar-driven H₂O₂ synthesis under both pure O₂ and air conditions even in harsh water environments (tap water, lake water, and seawater). Thus our study offers a new pathway for designing innovative catalysts for green chemical synthesis and environmental remediation.