Hydrogen-bond bridging dually facilitates exciton dissociation and charge migration for enhanced photocatalytic water oxidation.

As a kinetic bottleneck in artificial photosynthesis, the hole-mediated oxygen evolution reaction (OER) remains constrained by inefficient charge separation. We demonstrate here a hydrogen-bonded perylene diimide/aminated-fullerene (PDINH/C60NH3) supramolecular photocatalyst that concurrently enhances exciton dissociation efficiency (from 39.5% to 70.5%) and charge migration. The hydrogen bond between fullerene-tethered protonated amino and PDINH carbonyls creates a polarized bridge that enables exciton delocalization and conversion into weakly bound charge-transfer excitons, resulting in a significant decrease of exciton binding energy from 76.5 meV to 50.9 meV. Also, hydrogen-bond-induced charge polarization enhances the internal electric field by 3.5-fold, thereby accelerating charge migration and yielding a 19-fold increase in surface-reaching holes. Strikingly, PDINH/C60NH3 achieves a state-of-the-art OER rate of 63.9 mmol g-1 h-1 with remarkable apparent quantum efficiencies (11.83% at 420 nm and 4.08% at 650 nm). This hydrogen-bond-bridged charge separation establishes a new paradigm for enhancing solar-to-chemical conversion efficiency.