Plasmon-induced photothermal effect of sub-10-nm Cu nanoparticles enables boosted full-spectrum solar H-2 production

Distinguishing the contributions from localized surface plasmon resonance (LSPR)induced photothermal effect is a significant challenge in the study of solar hydrogen production. Herein, a well-defined one-dimensional Cu/TiO(2)heterostructure with Cu size of 3-6 nm is designed to address such issue. Cu nanoparticles present notable LSPR absorption from visible to near-infrared light, while no hydrogen is produced in the presence of simulated light with lambda >= 700 nm. Interestingly, a remarkable improvement of hydrogen evolution under full-spectrum light was observed which is almost twice of that under only ultraviolet-visible light irradiation, implying the critical yet auxiliary role of LSPR-induced photothermal effect in promoting photocatalytic performance. Significantly, a notable reduction of the apparent activation energy and strengthened charge separation efficiency are observed due to the increased local temperature of catalyst surface caused by the plasmon-induced photothermal effect. The kinetic and thermodynamic changes should be responsible for the enhanced hydrogen production.