2D/2D Hydrogen‐Bonded Organic Frameworks/Covalent Organic Frameworks S‐scheme Heterojunctions for Photocatalytic Hydrogen Evolution

Hydrogen‐bonded organic frameworks (HOFs) demonstrate significant potential for application in photocatalysis. However, the low efficiency of electron‐hole separation and limited stability inhibit their practical utilization in photocatalytic hydrogen evolution from water splitting. Herein, the novel dual‐pyrene‐base supramolecular HOF/COF 2D/2D S‐scheme heterojunction between HOF‐H4TBAPy (Py‐HOF, H4TBAPy represents the 1,3,6,8‐tetrakis (p‐benzoic acid) pyrene) and Py‐COF was successfully established using a rapid self‐assembly solution dispersion method. Experimental and theoretical investigations confirm that the size‐matching of two crystalline porous materials enables the integrated heterostructure material with abundant surface reaction sites, strong interaction, and an enhanced S‐scheme built‐in electric field, thus significantly improving the efficiency of photogenerated charge carrier separation and stability. Notably, the optimal HOF/COF heterojunction achieves a photocatalytic hydrogen evolution rate of 390.68 mmol g−1 h−1, which is 2.28 times higher than that of pure Py‐HOF and 9.24 times higher than that of pure COF. These findings precisely acquire valuable atomic‐scale insights into the ingenious design of dual‐pyrene‐based S‐scheme heterojunction. This work presents an innovative perspective for forming supramolecular S‐scheme heterojunctions over HOF‐based semiconductors, offering a protocol for designing the powerful and strong‐coupling S‐scheme built‐in electric fields for efficient solar energy utilization.