Lewis‐Base Coordination Enables Highly Dispersed Pt Cocatalyst on Pyrene‐Based MOFs for Enhanced Photocatalytic Hydrogen Evolution

ABSTRACT Rationally optimizing the coordination structures of Pt‐based cocatalysts to concurrently achieve enhanced charge separation/transfer and lowered reaction energy barriers is significant for photocatalysis. Herein, we engineered the coordination of Pt cocatalyst on pyrene‐based metal‐organic frameworks (MOFs) through grafting different Lewis‐base groups. The softness of the introduced groups directly determines their affinity for Pt precursors, allowing for precise tailoring of the electronic metal‐support interactions (EMSI) of Pt and MOFs, which leads to the distinct Pt coordination structures. These structural features accelerate charge separation/transfer by an established internal electric field and lower catalytic energy barriers enabled by the oxidized Pt surface, leading to significantly enhanced photocatalytic activity. Specifically, the ‐SH‐functionalized MOF (Pt/NU‐M), featuring strong EMSI, achieves atomic dispersion of Pt‐O/S coordination and delivers a superior hydrogen evolution rate of 5.68 mmol g cat −1 h −1 (405.71 mmol g pt −1 h −1 ) when using ascorbic acid as a sacrificial agent upon full‐spectrum light irradiation, which is about 16 times higher than that of the Pt/NU control and surpasses many reported MOF‐based materials. Notably, the catalyst maintains exceptional stability over 20 h of continuous operation. This work highlights Lewis‐base coordination for tailoring active sites and optimizing EMSI, providing new insights for rational catalyst design and related energy applications.