Photothermal-enhanced catalysis in core–shell plasmonic hierarchical Cu7S4 microsphere@zeolitic imidazole framework-8

Abstract

Conventional semiconductor photocatalysis based on band-edge absorption remains inefficient due to the limited harvesting of solar irradiation and the complicated surface/interface chemistry. Herein, novel photothermal-enhanced catalysis was achieved in a core–shell hierarchical Cu₇S₄ nano-heater@ZIF-8 heterostructures via near-infrared localized surface plasmon resonance. Our results demonstrated that both the high surface temperature of the photothermal Cu₇S₄ core and the close-adjacency of catalytic ZIF-8 shell contributed to the extremely enhanced catalytic activity. Under laser irradiation (1450 nm, 500 mW), the cyclocondensation reaction rate increased 4.5–5.4 fold compared to that of the process at room temperature, in which the 1.6–1.8 fold enhancement was due to the localized heating effect. The simulated sunlight experiments showed a photothermal activation efficiency (PTAE) of 0.07%, further indicating the validity of photothermal catalysis based on the plasmonic semiconductor nanomaterials. More generally, this approach provides a platform to improve reaction activity with efficient utilization of solar energy, which can be readily extended to other green-chemistry processes.