An LSPR-based “push–pull” synergetic effect for the enhanced photocatalytic performance of a gold nanorod@cuprous oxide-gold nanoparticle ternary composite

Abstract

As promising photocatalysts, nano-sized Cu₂O particles suffer from severe charge recombination and insufficient light absorption, resulting in their unsatisfactory photocatalytic performance. Herein, we have designed a core–shell structured Au nanorod@octahedron Cu₂O with preferentially edge-loaded Au nanoparticles (Au_(R)@Cu₂O–Au_(P)) for an efficient photocatalytic degradation reaction. A “push–pull” synergetic effect of Au_(R) and Au_(P) was found to improve the transfer and separation of charge carriers from the bulk to the surface of Cu₂O. Furthermore, the light beyond Cu₂O particles’ absorption range can penetrate the shell (Cu₂O) and for being utilized by the Au_(R) core via its localized surface plasmon resonance effect (LSPR) to inject hot electrons into the conduction band of Cu₂O for photocatalytic reactions. Moreover, the investigation of the size effect of Au_(R)@Cu₂O–Au_(P) reveals that both the short charge transfer distance and the more efficient charge transfer have contributed to its enhanced photocatalytic activity.