Cu single atom stabilized au nanoclusters on TiO₂ for efficient hydrogen production

Abstract

Metal nanoclusters (NCs) with atomically precise structures are widely used for light energy conversion in photocatalysis. However, the challenges in utilizing the photogenerated charges and light-induced photocatalyst instability often result in poor photocatalytic performance. Herein, we investigate tailoring of the local photocatalyst environment and promotion of the charge carrier transfer to increase the reactivity and stability of Auₙ/Cu–TiO₂ photocatalyst in photocatalytic hydrogen evolution from water under UVA illumination via in situ characterizations and theoretical calculations. The interfacial interaction between Au NCs and TiO₂ is regulated by precisely-anchored Cu single atoms (SAs) acting as electron acceptors, which can facilitate electron transfer from TiO₂ domains to Au NCs, thereby increasing the electron density of Au NCs, expedite electron capture, and enhance hydrogen production efficiency. As a result, Auₙ/Cu–TiO₂ exhibits 16.67 mmol·g⁻¹·h⁻¹ H₂ production rate, 22.7% apparent quantum yield, excellent photocatalytic stability, and recyclability under UVA light irradiation. This work offers novel insights into the rational design of semiconductor photocatalysts promoted with metal NCs and SAs, highlighting the cooperation effect in high photocatalytic performance.