内建电场与偶极场协同增强SnNb2O6/富氮C3N5 S型异质结光催化性能OA北大核心CSTPCD

Directional electron transfer is an appealing strategy for harnessing photogenerated charge separation kinetics.Herein,a novel 2D/1D SnNb2O6/nitrogen-enriched C3N5 S-scheme heterojunction with strong internal electric field(IEF)and dipole field(DF)is designed through in situ growth of C3N5 nanorods on SnNb2O6 nanosheets.The IEF generated at the interface via the formation of the S-scheme heterojunction induces directional charge transfer from SnNb2O6 to C3N5.Simultaneously,the DF within C3N5 provides the impetus to guide photo-excited electrons to the active sites.Consequently,the synergistic effects of IEF and DF facilitate swift directional electron transfer.The optimized SnNb2O6/C3N5 heterojunction demonstrates a remarkable H2 production rate of 1090.0 µmol·g-1·h-1 with continuous release of H2 bubbles.This performance surpasses that of SnNb2O6 and C3N5 by 38.8 and 10.7 times,respectively.Additionally,the SnNb2O6/C3N5 heterojunction exhibits superior activity in the removal of Rhodamine B,tetracycline,and Cr(VI).Based on electron paramagnetic resonance(EPR),time-resolved photoluminescence(TPRL)and density functional theory(DFT)calculations,etc.,the directional charge transfer mechanism was systematically explored.The research furnishes a plausible approach to construct effective heterojunction photocatalysts for applications in energy and environmental domains.