Chemically Bonded Plasmonic Triazole-Functionalized Au/Zeolitic Imidazole Framework (ZIF-67) for Enhanced CO2 Photoreduction.

The design of functionalized metallic nanoparticles is considered an emerging technique to ensure the interaction between metal and semiconductor material. In the literature, this interface interaction is mainly governed by electrostatic or van der Waals forces, limiting the injection of electrons under light irradiation. To enhance the transfer of electrons between two compounds, close contact or chemical bonding at the interface is required. Herein, a new approach was reported for the synthesis of chemically bonded plasmonic Au NPs/ZIF-67 nanocomposites. The structure of ZIF-67 was grown on the surface of functionalized plasmonic Au NPs using 1H-1,2,4-triazole-3-thiol as the capping agent, which acted as both stabilizer of Au nanoparticles and a molecular linker for ZIF-67 formation. As a result, the synthesized material exhibited outstanding photocatalytic CO2 reduction with a methanol production rate of 2.70 mmol h-1 g-1 cat under sunlight irradiation. This work emphasizes that the diligent use of capping agents, with suitable functional groups, could facilitate the formation of intimate heterostructure for enhanced photocatalytic CO2 reduction.