Reverse Replacement in NH₂ -MIL-125 with 1,4-Dicarboxybenzene for Enhanced Photocatalytic Hydrogen Generation

Metal-organic frameworks (MOFs) constructed by ligands and metal clusters, have been considered as a promising material for photocatalytic water splitting. In this work, a solvent-assisted ligand exchange (SALE) method has been applied through partial reverse substitution of the ligand in NH₂ -MIL-125 (Ti) by 1,4-dicarboxybenzene (BDC). This modification strategy can optimize the charge transfer dynamics together with the preserved light absorption, resulting in a 3.3 times higher hydrogen production rate compared to the pristine material under visible-light irradiation. This work broadens the field of ligand modifications of MOFs to boost the photocatalytic performance.