In Situ Topochemical Transformation of ZnIn₂S₄ for Efficient Photocatalytic Oxidation of 5‐Hydroxymethylfurfural to 2,5‐Diformylfuran

Abstract Photocatalytic selective oxidation of 5‐hydroxymethylfurfural (HMF) coupled H 2 production offers a promising approach to producing valuable chemicals. Herein, an efficient in situ topological transformation tactic is developed for producing porous O‐doped ZnIn 2 S 4 nanosheets for HMF oxidation cooperative with H 2 evolution. Aberration‐corrected high‐angle annular dark‐field scanning TEM images show that the hierarchical porous O‐ZIS‐120 possesses abundant atomic scale edge steps and lattice defects, which is beneficial for electron accumulation and molecule adsorption. The optimal catalyst (O‐ZIS‐120) exhibits remarkable performance with 2,5‐diformylfuran (DFF) yields of 1624 µmol h −1 g −1 and the selectivity of >97%, simultaneously with the H 2 evolution rate of 1522 µmol h −1 g −1 . Mechanistic investigations through theoretical calculations show that O in the O‐ZIS‐120 lattice can reduce the oxidation energy barrier of hydroxyl groups of HMF. In situ attenuated total reflection surface‐enhanced infrared absorption spectroscopy (ATR‐SEIRAS) results reveal that DFF * (C 4 H 2 (CHO) 2 O * ) intermediate has a weak interaction with O‐ZIS‐120 and desorb as the final product. This study elucidates the topotactic structural transitions of 2D materials simultaneously with electronic structure modulation for efficient photocatalytic DFF production.