Cadmium sulfide(Cd S)-based photocatalysts have attracted extensive attention owing to their strong visible light absorption,suitable band energy levels,and excellent electronic charge transportation properties.This r...Cadmium sulfide(Cd S)-based photocatalysts have attracted extensive attention owing to their strong visible light absorption,suitable band energy levels,and excellent electronic charge transportation properties.This review focuses on the recent progress related to the design,modification,and construction of Cd S-based photocatalysts with excellent photocatalytic H2 evolution performances.First,the basic concepts and mechanisms of photocatalytic H2 evolution are briefly introduced.Thereafter,the fundamental properties,important advancements,and bottlenecks of Cd S in photocatalytic H2 generation are presented in detail to provide an overview of the potential of this material.Subsequently,various modification strategies adopted for Cd S-based photocatalysts to yield solar H2 are discussed,among which the effective approaches aim at generating more charge carriers,promoting efficient charge separation,boosting interfacial charge transfer,accelerating charge utilization,and suppressing charge-induced self-photocorrosion.The critical factors governing the performance of the photocatalyst and the feasibility of each modification strategy toward shaping future research directions are comprehensively discussed with examples.Finally,the prospects and challenges encountered in developing nanostructured Cd S and Cd S-based nanocomposites in photocatalytic H2 evolution are presented.展开更多
As a low-cost visible-light-driven metal-free catalyst, graphitic carbon nitride(g-CN) has attracted increasing attention due to its wide applications for solar energy conversion, environmental purification,and organi...As a low-cost visible-light-driven metal-free catalyst, graphitic carbon nitride(g-CN) has attracted increasing attention due to its wide applications for solar energy conversion, environmental purification,and organic photosynthesis. In particular, the catalytic performance of g-CNcan be easily modulated by modifying morphology, doping, and copolymerization. Simultaneous optimization, however, has little been achieved. Herein, a facile one-pot strategy is developed to synthesize porous B-doped g-CNnanosheets by using HBOand urea as the precursor during thermal polymerization. The resultant B-doped g-CNnanosheets retain the original framework of bulk g-CN, while induce prominently enhanced visible light harvesting and narrowing band gap by 0.32 eV compared to pure g-CN. Moreover, the adsorption capacity and photodegradation kinetics of methylene blue(MB) under visible light irradiation over B-doped g-CNnanosheets can be improved by 20.5 and 17 times, respectively. The synthesized porous B-doped g-CNnanosheets also exhibit higher activities than pure g-CNas bifunctional electrocatalyst for both oxygen evolution reaction(OER) and oxygen reduction reaction(ORR). The enhanced catalyst performance of porous B-doped g-CNnanosheets stems from the strong synergistic effect originating from the larger exposed active sites generated by the exfoliation of g-CNinto nanosheets and the porous structure, as well as the better conductivity owing to B-doping. This work provides a simple, effective, and robust method for the synthesis of g-CN-based nanomaterial with superior properties to meet the needs of various applications.展开更多
With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4...With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4）. The resulting g-C3N4/Vo-ZnO hybrid photocatalysts showed higher visible-light photocatalytic activity than pure Vo-ZnO and g-C3N4. The hybrid photocatalyst with a g-C3N4 content of 1 wt% exhibited the highest photocatalytic degradation activity under visible-light irradiation（λ≥ 400 nm）. In addition,the g-C3N4/Vo-ZnO photocatalyst was not deactivated after five cycles of methyl orange degradation,indicating that it is stable under light irradiation. Finally,a Z-scheme mechanism for the enhanced photocatalytic activity and stability of the g-C3N4/Vo-ZnO hybrid photocatalyst was proposed. The fast charge separation and transport within the g-C3N4/Vo-ZnO hybrid photocatalyst were attributed as the origins of its enhanced photocatalytic performance.展开更多
基金the National Natural Science Foundation of China(21975084 and 51672089)the Ding Ying Talent Project of South China Agricultural University for their support+1 种基金the Hong Kong Research Grant Council(RGC)General Research Fund GRF1305419 for financial supportthe National Natural Science Foundation of China(51972287 and 51502269)。
文摘Cadmium sulfide(Cd S)-based photocatalysts have attracted extensive attention owing to their strong visible light absorption,suitable band energy levels,and excellent electronic charge transportation properties.This review focuses on the recent progress related to the design,modification,and construction of Cd S-based photocatalysts with excellent photocatalytic H2 evolution performances.First,the basic concepts and mechanisms of photocatalytic H2 evolution are briefly introduced.Thereafter,the fundamental properties,important advancements,and bottlenecks of Cd S in photocatalytic H2 generation are presented in detail to provide an overview of the potential of this material.Subsequently,various modification strategies adopted for Cd S-based photocatalysts to yield solar H2 are discussed,among which the effective approaches aim at generating more charge carriers,promoting efficient charge separation,boosting interfacial charge transfer,accelerating charge utilization,and suppressing charge-induced self-photocorrosion.The critical factors governing the performance of the photocatalyst and the feasibility of each modification strategy toward shaping future research directions are comprehensively discussed with examples.Finally,the prospects and challenges encountered in developing nanostructured Cd S and Cd S-based nanocomposites in photocatalytic H2 evolution are presented.
文摘As a low-cost visible-light-driven metal-free catalyst, graphitic carbon nitride(g-CN) has attracted increasing attention due to its wide applications for solar energy conversion, environmental purification,and organic photosynthesis. In particular, the catalytic performance of g-CNcan be easily modulated by modifying morphology, doping, and copolymerization. Simultaneous optimization, however, has little been achieved. Herein, a facile one-pot strategy is developed to synthesize porous B-doped g-CNnanosheets by using HBOand urea as the precursor during thermal polymerization. The resultant B-doped g-CNnanosheets retain the original framework of bulk g-CN, while induce prominently enhanced visible light harvesting and narrowing band gap by 0.32 eV compared to pure g-CN. Moreover, the adsorption capacity and photodegradation kinetics of methylene blue(MB) under visible light irradiation over B-doped g-CNnanosheets can be improved by 20.5 and 17 times, respectively. The synthesized porous B-doped g-CNnanosheets also exhibit higher activities than pure g-CNas bifunctional electrocatalyst for both oxygen evolution reaction(OER) and oxygen reduction reaction(ORR). The enhanced catalyst performance of porous B-doped g-CNnanosheets stems from the strong synergistic effect originating from the larger exposed active sites generated by the exfoliation of g-CNinto nanosheets and the porous structure, as well as the better conductivity owing to B-doping. This work provides a simple, effective, and robust method for the synthesis of g-CN-based nanomaterial with superior properties to meet the needs of various applications.
基金supported by the National Basic Research Program of China(2011CB933700)the National Natural Science Foundation of China(21271165)~~
文摘With the objectives of enhancing the stability,optical properties and visible-light photocatalytic activity of photocatalysts,we modified oxygen vacancy-rich zinc oxide（Vo-ZnO） with graphitic carbon nitride（g-C3N4）. The resulting g-C3N4/Vo-ZnO hybrid photocatalysts showed higher visible-light photocatalytic activity than pure Vo-ZnO and g-C3N4. The hybrid photocatalyst with a g-C3N4 content of 1 wt% exhibited the highest photocatalytic degradation activity under visible-light irradiation（λ≥ 400 nm）. In addition,the g-C3N4/Vo-ZnO photocatalyst was not deactivated after five cycles of methyl orange degradation,indicating that it is stable under light irradiation. Finally,a Z-scheme mechanism for the enhanced photocatalytic activity and stability of the g-C3N4/Vo-ZnO hybrid photocatalyst was proposed. The fast charge separation and transport within the g-C3N4/Vo-ZnO hybrid photocatalyst were attributed as the origins of its enhanced photocatalytic performance.
