In Situ Fabrication of Porous MOF/COF Hybrid Photocatalysts for Visible-Light-Driven Hydrogen Evolution

Construction of porous metal-organic framework (MOF)/covalent organic framework (COF) hybrid photocatalysts for enriched structures and unprecedented properties is still a great challenge but highly desirable. Herein, a new series of Cu₃(HHTP)₂-MOF/Tp-Pa-1-COF hybrids with different MOF content are successfully fabricated. The as-prepared MOF/COF hybrids exhibit intimate interaction based on the coordination of Cu ions with the carbonyl oxygen and enamine nitrogen groups in Tp-Pa-1. The integrated conductive Cu₃(HHTP)₂ is able to act as an excellent electron extractor instead of noble metal cocatalysts to significantly promote the charge transfer and inhibit the recombination of photogenerated electron-hole pairs. As a results, the optimized photocatalyst with Cu₃(HHTP)₂:Tp-Pa-1 ratio of 1:15 achieves the highest hydrogen evolution rate of 1.76 mmol·h^-1·g^-1 under visible-light irradiation, which is about 93 times higher than that of the pure Tp-Pa-1 and even slightly higher than that of the Tp-Pa-1 with Pt (3 wt %) as a cocatalyst.