Single-site oxidation-directed topological evolution of hydrogen-bonded organic frameworks for efficient photocatalysis

Photocatalytic hydrogen peroxide synthesis offers a green alternative to the energy-intensive anthraquinone process. However, hydrogen-bonded organic frameworks remain underexplored in this field due to their limited stability and lack of photoactive units. In this work, we modulate the oxidation state of photosensitive structural motifs to precisely direct topological evolution of hydrogen-bonded organic frameworks at a single site. Stepwise oxidation of the sulfur center enhances framework stability and optimizes hydrogen-bonding networks and charge transport pathways. PTH-SO2-HOF exhibits high charge separation efficiency, delivering a competitive hydrogen peroxide production rate of 2480 μmol g-1 h-1 in pure water, which reaches 5329 μmol g-1 h-1 with a sacrificial agent. Mechanistic studies reveal synergistic interplay between the higher oxidation state and hydrogen-bonding network in promoting the oxygen reduction pathway. This work provides a new strategy for designing robust and efficient hydrogen-bonded organic frameworks for photocatalysis. A strategy of oxidation-state engineering enables topological control of hydrogen-bonded organic frameworks, yielding a material with high stability and charge separation efficiency that achieves competitive photocatalytic H2O2 production.