Merging semi-crystallization and multispecies iodine intercalation at photo-redox interfaces for dual high-value synthesis.

The artificial photocatalytic synthesis based on graphitic carbon nitride (g-C 3 N 4 ) for H 2 O 2 production is evolving rapidly. However, the simultaneous production of high-value products at electron and hole sites remains a great challenge. Here, we use transformable potassium iodide to obtain semi-crystalline g-C 3 N 4 integrated with the I - /I 3 - redox shuttle mediators for efficient generation of H 2 O 2 and benzaldehyde. The system demonstrates a prominent catalytic efficiency, with a benzaldehyde yield of 0.78 mol g -1 h -1 and an H 2 O 2 yield of 62.52 mmol g -1 h -1 . Such a constructed system can achieve an impressive 96.25% catalytic selectivity for 2e - oxygen reduction, surpassing previously reported systems. The mechanism study reveals that the strong crystal electric field from iodized salt enhances photo-generated charge carrier separation. The I - /I 3 - redox mediators significantly boost charge migration and continuous electron and proton supply for dual-channel catalytic synthesis. This groundbreaking work in photocatalytic co-production opens neoteric avenues for high-value synthesis.