Constructing heterojunction photocatalysts is a highly effective strategy for achieving overall water splitting,particularly by overcoming the challenge of sluggish electron-hole transport.This study employed a defect...Constructing heterojunction photocatalysts is a highly effective strategy for achieving overall water splitting,particularly by overcoming the challenge of sluggish electron-hole transport.This study employed a defect-induced in situ growth approach to anchor NiSe onto carbon-vacancy-rich C_(3)N_(5)(C_(v)-C_(3)N_(5)),forming interfacial Ni-N bonds.The resulting NiSe/C_(v)-C_(3)N_(5)heterojunction exhibited stoichiometric H_(2)and O_(2)evolution rates of 1956.1 and 989.1μmol g^(-1)h^(-1),respectively,8.4 times higher than a counterpart lacking interfacial bonding.Both theoretical calculations and experimental data confirmed that the Ni–N bonds were instrumental in enhancing photocatalytic performance by inducing and reinforcing S-scheme charge transfer.Illumination X-ray photoelectron spectroscopy analysis revealed that a synergistic charge transfer pathway:photoexcited electrons from the NiSe conduction band migrated sequentially to Ni atoms,then to N atoms,and ultimately recombined with holes in the C_(v)-C_(3)N_(5)valence band.Moreover,these interfacial bonds significantly lowered the energy barrier and shortened the transport distance for electron transfer,amplifying the built-in interfacial electric field and accelerating charge dynamics.This study provides critical insights into the rational design of heterojunction photocatalysts for efficient water splitting.展开更多
文摘Constructing heterojunction photocatalysts is a highly effective strategy for achieving overall water splitting,particularly by overcoming the challenge of sluggish electron-hole transport.This study employed a defect-induced in situ growth approach to anchor NiSe onto carbon-vacancy-rich C_(3)N_(5)(C_(v)-C_(3)N_(5)),forming interfacial Ni-N bonds.The resulting NiSe/C_(v)-C_(3)N_(5)heterojunction exhibited stoichiometric H_(2)and O_(2)evolution rates of 1956.1 and 989.1μmol g^(-1)h^(-1),respectively,8.4 times higher than a counterpart lacking interfacial bonding.Both theoretical calculations and experimental data confirmed that the Ni–N bonds were instrumental in enhancing photocatalytic performance by inducing and reinforcing S-scheme charge transfer.Illumination X-ray photoelectron spectroscopy analysis revealed that a synergistic charge transfer pathway:photoexcited electrons from the NiSe conduction band migrated sequentially to Ni atoms,then to N atoms,and ultimately recombined with holes in the C_(v)-C_(3)N_(5)valence band.Moreover,these interfacial bonds significantly lowered the energy barrier and shortened the transport distance for electron transfer,amplifying the built-in interfacial electric field and accelerating charge dynamics.This study provides critical insights into the rational design of heterojunction photocatalysts for efficient water splitting.
