A new strategy for the fabrication of covalent organic framework-metal-organic framework hybrids via in-situ functionalization of ligands for improved hydrogen evolution reaction activity

The development of novel porous materials have attracted significant attention owing to its possible application in several fields. In this study, we designed a novel covalent organic framework-metal-organic framework (COF-MOF) material through an in-situ ligand self-assembly method. The in-situ modified ligands not only act as nucleation sites to form Ti-MOF, but also as a channel to rapidly transfer photogenerated electrons without introducing additional chemical bonds. The photocatalytic hydrogen production rate achieved over B-CTF-Ti-MOF(1:1) was 1975 µmol·g−1·h−1 with an apparent quantum efficiency of 4.76%, which is 11.8 times higher than that of the pure CTF-1. In addition, compared with the sample prepared by separating the ligands (CTF-1/Ti-MOF), B-CTF-Ti-MOF shows excellent activity and stability. Finally, a reasonable photocatalytic mechanism was proposed using the results of electrochemical tests and spectral analyses. This study provides a universal method for the construction of highly efficient and stable COF/MOF materials with excellent properties.