Facile construction of metal–organic frameworks/topological insulator heterostructure for photothermal catalytic CO2 reduction

Abstract

Photothermal catalytic CO₂ reduction, which combines the advantages of photocatalysis and the photothermal effect, has emerged as one of the most promising strategies to meet the global energy crisis and prevent excessive carbon emission. As a well-known topological insulator, bismuth selenide (Bi₂Se₃) has evoked extensive research attention due to its narrow bandgap, distinctive surface metallic states, and excellent photothermal conversion performance. Herein, we report a metal–organic framework/topological insulator heterostructure, constructed using a representative MOF ZIF-8 and Bi₂Se₃ nanosheets (Bi₂Se₃ NSs). Notably, the as-prepared ZIF-8/Bi₂Se₃ NSs heterostructure exhibits remarkable near-infrared light harvesting ability and thus presents an enhanced photo-to-heat conversion performance with an increase of surface temperature to 67 °C upon UV-Vis-NIR light irradiation within 60 s. Moreover, the ZIF-8/Bi₂Se₃ NSs heterostructure delivers better photothermal catalytic CO₂ reduction activity with a CO generation rate of 22.65 μmol g⁻¹ h⁻¹, which is 2.83 times that of ZIF-8/Bi₂Se₃ nanoparticles (Bi₂Se₃ NPs). The superior photothermal catalytic performance of the ZIF-8/Bi₂Se₃ NSs heterostructure is ascribed to the efficient separation and transfer of photogenerated charge carriers, coupled with the synergetic effect of photo-to-heat conversion induced by the abundant surface metallic states in layered Bi₂Se₃ NSs. This work will provide new insights for the development of novel and efficient photothermal catalysts in the future.