(GO/TiO2)N(GO represents graphene oxide,and N represents the period number of alternate superposition of two dielectrics)onedimensional photonic crystal with different lattice constants was prepared via the sol–gel t...(GO/TiO2)N(GO represents graphene oxide,and N represents the period number of alternate superposition of two dielectrics)onedimensional photonic crystal with different lattice constants was prepared via the sol–gel technique,and its transmission characteristics for photocatalysis were tested.The results show that the lattice constant,filling ratio,number of periodic layers,and incident angle had effects on the band gap.When the lattice constant,filling ratio,number of periodic layers,and incident angle were set to 125 nm,0.45,21,and 0°,respectively,a gap width of 53 nm appeared at the central wavelength(322 nm).The absorption peak of the photocatalyst at 357 nm overlapped the blue edge of the photonic band gap.A slow photon effect region above 96%reflectivity appeared.The degradation rate of tetracycline in(GO/TiO2)N photonic crystal was enhanced to 64%within 60 min.Meanwhile,the degradation efficiency of(GO/TiO2)N one-dimensional photonic crystal was effectively improved compared with those of the GO/TiO2 composite film and GO/TiO2 powder.展开更多
In photocatalysis,both the photogenerated charge separation and transport and the induced light utilization greatly influence performance.In this work,highly ordered CdS@ZnO core-shell inverse opal(CdS@ZnO-csIO)nanoco...In photocatalysis,both the photogenerated charge separation and transport and the induced light utilization greatly influence performance.In this work,highly ordered CdS@ZnO core-shell inverse opal(CdS@ZnO-csIO)nanocomposites have been successfully designed as a model to couple the heterojunction system with the slow photon effect for photocatalytic H2 production.Theoretical calculations and experimentation provide direct evidence for the slow photon effect in the CdS@ZnO-csIO nanocomposites.The type II heterojunction is responsible for promoting the migration and separation of photogenerated charges,and the slow photon effect is in charge of enhancing light harvesting in the CdS@ZnO-csIO nanocomposites.This synergy of two functions gives rise to a significantly enhanced photocatalytic H2 production rate under simulated solar light for the CdS@ZnO-csIO nanocomposites.The highest H2 production rate reaches 48.7 mmol g^(−1)h^(−1)under simulated solar light with the benchmark performance for all reported CdS@ZnO composites.Our work provides proof-of-principle that coupling the heterojunction system with the slow photon effect can greatly enhance the photocatalytic activity of composite photocatalysts.展开更多
基金the National Key R&D Program of China(No.2016YFC0700904)。
文摘(GO/TiO2)N(GO represents graphene oxide,and N represents the period number of alternate superposition of two dielectrics)onedimensional photonic crystal with different lattice constants was prepared via the sol–gel technique,and its transmission characteristics for photocatalysis were tested.The results show that the lattice constant,filling ratio,number of periodic layers,and incident angle had effects on the band gap.When the lattice constant,filling ratio,number of periodic layers,and incident angle were set to 125 nm,0.45,21,and 0°,respectively,a gap width of 53 nm appeared at the central wavelength(322 nm).The absorption peak of the photocatalyst at 357 nm overlapped the blue edge of the photonic band gap.A slow photon effect region above 96%reflectivity appeared.The degradation rate of tetracycline in(GO/TiO2)N photonic crystal was enhanced to 64%within 60 min.Meanwhile,the degradation efficiency of(GO/TiO2)N one-dimensional photonic crystal was effectively improved compared with those of the GO/TiO2 composite film and GO/TiO2 powder.
基金supported by the National Key R&D Program of China(grant nos.2016YFA0202602 and 2021YFE0115800)the National Natural Science Foundation of China(grant nos.U20A20122 and 52103285)+3 种基金the 111 National Project(grant no.B20002)the Natural Science Foundation of Hubei Province(grant no.2020CFB416)the Fundamental Research Funds for the Central Universities(grant no.WUT:2021III016GX)the Open Fund Project of the State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology,2021-KF-1).Youth Innovation Research Fund project of State Key Laboratory of Advanced Technology for Materials Synthesis and Processing(Wuhan University of Technology).
文摘In photocatalysis,both the photogenerated charge separation and transport and the induced light utilization greatly influence performance.In this work,highly ordered CdS@ZnO core-shell inverse opal(CdS@ZnO-csIO)nanocomposites have been successfully designed as a model to couple the heterojunction system with the slow photon effect for photocatalytic H2 production.Theoretical calculations and experimentation provide direct evidence for the slow photon effect in the CdS@ZnO-csIO nanocomposites.The type II heterojunction is responsible for promoting the migration and separation of photogenerated charges,and the slow photon effect is in charge of enhancing light harvesting in the CdS@ZnO-csIO nanocomposites.This synergy of two functions gives rise to a significantly enhanced photocatalytic H2 production rate under simulated solar light for the CdS@ZnO-csIO nanocomposites.The highest H2 production rate reaches 48.7 mmol g^(−1)h^(−1)under simulated solar light with the benchmark performance for all reported CdS@ZnO composites.Our work provides proof-of-principle that coupling the heterojunction system with the slow photon effect can greatly enhance the photocatalytic activity of composite photocatalysts.
