Construction of Core–Shell MOF@COF Hybrids with Controllable Morphology Adjustment of COF Shell as a Novel Platform for Photocatalytic Cascade Reactions

Recently, novel core–shell MOF@COF hybrids display excellent performance in various fields because of their inherited advantages from their parent MOFs and/or COFs. However, it is still a grand challenge to adjust the morphology of MOFs and/or COFs for consequent performance improvement. Herein, a Ti‐MOF@TpTt hybrid coated with ultra‐thin COF nanobelt, which is different from the fibrillar‐like parent COF, is successfully synthesized through a sequential growth strategy. The as‐obtained Pd decorated Ti‐MOF@TpTt catalyst exhibits much higher photocatalytic performance than those of Ti‐MOF, TpTt‐COF, and Ti‐MOF@TpTt hybrids with fibrillar‐like COF shell for the photocatalytic cascade reactions of ammonia borane (AB) hydrolysis and nitroarenes hydrogenation. These can be attributed to its high BET surface area, core–shell structure, and type II heterojunction, which offers more accessible active sites and improves the separation efficiency of photo‐generated carriers. Finally, the possible mechanisms of the cascade reaction are also proposed to well explain the improved performance of this photocatalytic system. This work presents a constructive route for designing core–shell MOF@COF hybrids with controllable morphology adjustment of COF shell, leading to the improved photocatalytic ability to broaden the applications of MOF/COF hybrid materials.