Construction of double-functionalized g-C3N4 heterojunction structure via optimized charge transfer for the synergistically enhanced photocatalytic degradation of sulfonamides and H2O2 production

Herein, supporting g-C3N4 embedded with benzene-ring (BCN) on P-modified g-C3N4 (PCN) successfully synthesized the homogeneous photocatalyst BCN/PCN (PBCN) via a simple thermal polymerization reaction. Under blue-light (LED) irradiation, the optimized PBCN (0.448 min(-1)) demonstrated excellent photocatalytic performance, attaining over 74 times the degradation rate for sulfisoxazole (SSZ) in contrast to non-functionalized g-C3N4 (CN, 0.006 min(-1)). Theoretical calculations revealed that the substitution of heterocyclic rings in the g-C(3)N4 triazine networks with benzene-rings enabled them to serve as electron donors, while promoting photo-induced spatial charge dissociation. Further, the carrier PCN tended to serve as electron acceptors to form electron-rich corner-phosphorous sites. Reactive species experiments demonstrate that the O(2)(- )and h(+) constituted the primary photocatalytic mechanism of SSZ degradation. The potential SSZ degradation routes were predicted based on the transformation products via mass spectrometry. Finally, the composite materials also exhibited excellent photocatalytic activity in the conversion of solar energy to chemical energy (H2O2). This study guides the rational modification of g-C(3)N4-based semiconductors to achieve green energy production and beneficial ecological applications.

Automated summary

The study successfully synthesized the photocatalyst BCN/PCN, which showed excellent photocatalytic performance under blue-light irradiation, especially in the degradation of SSZ. The research revealed the mechanism of SSZ photocatalytic degradation and potential reaction pathways, while also demonstrating the application potential of the material in converting solar energy to chemical energy.