Rejoint of Carbon Nitride Fragments into Multi‐Interfacial Order‐Disorder Homojunction for Robust Photo‐Driven Generation of H₂O₂

Abstract Photocatalytic technology based on carbon nitride (C₃N₄) offers a sustainable and clean approach for hydrogen peroxide (H₂O₂) production, but the yield is severely limited by the sluggish hot carriers due to the weak internal electric field. In this study, a novel approach is devised by fragmenting bulk C₃N₄ into smaller pieces (CN‐NH₄) and then subjecting it to a directed healing process to create multiple order‐disorder interfaces (CN‐NH₄‐NaK). The resulting junctions in CN‐NH₄‐NaK significantly boost charge dynamics and facilitate more spatially and orderly separated redox centers. As a result, CN‐NH₄‐NaK demonstrates outstanding photosynthesis of H₂O₂ via both two‐step single‐electron and one‐step double‐electron oxygen reduction pathways, achieving a remarkable yield of 16675 µmol h^–1 g^–1, excellent selectivity (> 91%), and a prominent solar‐to‐chemical conversion efficiency exceeding 2.3%. These remarkable results surpass pristine C₃N₄ by 158 times and outperform previously reported C₃N₄‐based photocatalysts. This work represents a significant advancement in catalyst design and modification technology, inspiring the development of more efficient metal‐free photocatalysts for the synthesis of highly valued fuels.