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
In this study,CdS/ZnO(2:3 mol%)thin films are successfully deposited on quartz substrates by using the sputtering technique.Good images on the structural and optical characteristic features of CdS/ZnO thin films befor...In this study,CdS/ZnO(2:3 mol%)thin films are successfully deposited on quartz substrates by using the sputtering technique.Good images on the structural and optical characteristic features of CdS/ZnO thin films before and after annealing are obtained.The CdS/ZnO thin films are annealed respectively at temperatures of 373 K,473 K,and 573 K and the structural features are examined by XRD,ATR-FTIR,and FESEM.The optical properties of CdS/ZnO thin films such as refractive indices,absorption coefficients,optical band gap energy values,Urbach energy values,lattice dielectric constants,and high frequency dielectric constants are determined from spectrophotometer data recorded over the spectral range of 300 nm-2500 nm.Dispersion parameters are investigated by using a single-oscillator model.Photoluminescence spectra of CdS/ZnO thin films show an overall decrease in their intensity peaks after annealing.The third-order nonlinear optical parameter,and nonlinear refractive index are also estimated.展开更多
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.
基金the Deanship of Scientific Research,Taif University,Kingdom of Saudi Arabia(Grant No.1-440-6136).
文摘In this study,CdS/ZnO(2:3 mol%)thin films are successfully deposited on quartz substrates by using the sputtering technique.Good images on the structural and optical characteristic features of CdS/ZnO thin films before and after annealing are obtained.The CdS/ZnO thin films are annealed respectively at temperatures of 373 K,473 K,and 573 K and the structural features are examined by XRD,ATR-FTIR,and FESEM.The optical properties of CdS/ZnO thin films such as refractive indices,absorption coefficients,optical band gap energy values,Urbach energy values,lattice dielectric constants,and high frequency dielectric constants are determined from spectrophotometer data recorded over the spectral range of 300 nm-2500 nm.Dispersion parameters are investigated by using a single-oscillator model.Photoluminescence spectra of CdS/ZnO thin films show an overall decrease in their intensity peaks after annealing.The third-order nonlinear optical parameter,and nonlinear refractive index are also estimated.