Marrying luminescent metal nanoclusters to C3N4 for efficient photocatalytic hydrogen peroxide production

Photocatalytic oxygen (O2) reduction has been considered a promising method for hydrogen peroxide (H2O2) production. However, the poor visible light harvesting and low-efficient separation and generation of charge carriers of conventional photocatalysts strongly limited their photocatalytic H2O2 generation performance. Herein, we design a highly efficient photocatalyst in this work by marrying luminescent gold-silver nanoclusters (AuAg NCs) to polyethyleneimine (PEI) modified C3N4 (C3N4-PEI). The key design in this work is the utilization of highly luminescent AuAg NCs as photosensitizers to promote the generation and separation of charge carriers of C3N4-PEI, thereby ultimately producing abundant e− for O2 reduction under visible light illumination (λ ≥ 400 nm). As a result, the as-designed photocatalyst (C3N4-PEI-AuAg NCs) exhibits excellent photocatalytic activity with an H2O2 production capability of 82 μM in pure water, which is 3.5 times higher than pristine C3N4 (23 μM). This interesting design provides a paradigm in developing other high-efficient photocatalysts for visible-light-driven H2O2 production.