Plasmon-induced interfacial charge-transfer transition prompts enhanced CO2 photoreduction over Cu/Cu2O octahedrons
Abstract The plasmon-induced interfacial charge-transfer transition (PICTT) involves the direct electron transfer from a plasmonic metal to the acceptor state in a semiconductor (SC). Such plasmonic decay is fostered by strong orbital coupling and mixing of electronic levels in plasmonic metals and SC. Although the effectiveness of PICTT for charge transfer has been testified, its realization still remains a great challenge. Herein, we employed a facile electroless reduction strategy for the in-situ growth of copper (Cu) nanoparticles (NPs) over Cu2O ordered octahedrons. Amorphous carbon formed at the Cu2O surface via calcination provides an electroless reduction configuration for the conversion of Cu ions within Cu2O lattice into Cu NPs. The in-situ growth guarantees a rational couple of Cu2O with its derivative Cu NPs. Such a unique arrangement enables extension of optical absorption range as well as achievement of PICTT upon excitation of Cu-localized surface plasmon resonance (LSPR), which promotes desirable CO2 photoreduction activity under near-infrared irradiation. This work provides an effective strategy for constructing plasmonic-metal/metal-oxide composites with enhanced photocatalytic efficiency.