A novel efficient Cu_(2)WS_(4)/MoS_(2) step-scheme(S-scheme)heterojunction photocatalyst was constructed for the first time and applied in the removal of environmental pollutants.Among the as-prepared photocatalysts,t...A novel efficient Cu_(2)WS_(4)/MoS_(2) step-scheme(S-scheme)heterojunction photocatalyst was constructed for the first time and applied in the removal of environmental pollutants.Among the as-prepared photocatalysts,the Cu_(2)WS_(4)/MoS_(2)-8%heterojunc tion photoc atalyst demonstrates the optimal photocatalytic performance,with the catalytic oxidation efficiency of tetracycline(TC)and the catalytic reduction efficiency of Cr^(6+)reaching 93.3%and 82.1%,respectively.The excellent catalytic properties of Cu_(2)WS_(4)/MoS_(2) heterojunction photocatalysts are attributed to the effective separation pathways of charges and the presence of S-scheme heterojunctions,together with stronger redox capabilities.It is speculated that the photogenerated carrier migration path of the Cu_(2)WS_(4)/MoS_(2) catalyst follows the typical S-scheme photocatalytic mechanism,which is verified by the in-depth experimental study and simulated calculations including the electron paramagnetic resonance(EPR)analysis,free radical quenching experiments,charge density distribution,and simulated built-in electric field formation at the interface,which acts as driving force to promote the separation of photoinduced electrons and holes.Finally,the photocatalytic mechanism of S-scheme photogenerated carrier migration for the Cu_(2)WS_(4)/MoS_(2) catalyst is revealed based on the systematic experimental techniques and simulated calculations,accounting for its superior photocatalytic oxidation and reduction activities.This study provides inspiring implications to develop high-efficient S-scheme photocatalytic systems for versatile applications in solarenergy conversion.展开更多
Inexpensive,safe,and efficient conversion of solar energy to hydrogen from water splitting requires the development of effective and durable photocatalysts.Cu_(2)ZnSnS_(4)(CZTS),the emerging quaternary chalcogenide ma...Inexpensive,safe,and efficient conversion of solar energy to hydrogen from water splitting requires the development of effective and durable photocatalysts.Cu_(2)ZnSnS_(4)(CZTS),the emerging quaternary chalcogenide material for solar energy conversion,possesses many advantages,such as narrow direct band gap(1.5 eV),nontoxic,earth-abundance,and low melting point.Currently,CZTS-based photocatalysts have been extensively investigated for their application as an active photocatalyst in hydrogen evolution from water splitting,while the performance is still highly needed to be improved for the practical applications.In this review,first,the crystal and band structure properties of CZTS are briefly introduced,and afterward,the basic principle of photocatalytic hydrogen evolution from water splitting is discussed.Subsequently,the performance and status of bare CZTS,the combination of CZTS and co-catalysts,and CZTSbased heterojunction photocatalysts for hydrogen evolution are reviewed and discussed in detail.Finally,the issues and challenges currently encountered in the application of CZTS and their possible solutions for developing advanced CZTS photocatalysts are provided.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.52000011,62274017 and 51808250)the Natural Science Foundation of Jiangsu Province of China(No.BK20210041)the Hong Kong Scholars Program 2017。
文摘A novel efficient Cu_(2)WS_(4)/MoS_(2) step-scheme(S-scheme)heterojunction photocatalyst was constructed for the first time and applied in the removal of environmental pollutants.Among the as-prepared photocatalysts,the Cu_(2)WS_(4)/MoS_(2)-8%heterojunc tion photoc atalyst demonstrates the optimal photocatalytic performance,with the catalytic oxidation efficiency of tetracycline(TC)and the catalytic reduction efficiency of Cr^(6+)reaching 93.3%and 82.1%,respectively.The excellent catalytic properties of Cu_(2)WS_(4)/MoS_(2) heterojunction photocatalysts are attributed to the effective separation pathways of charges and the presence of S-scheme heterojunctions,together with stronger redox capabilities.It is speculated that the photogenerated carrier migration path of the Cu_(2)WS_(4)/MoS_(2) catalyst follows the typical S-scheme photocatalytic mechanism,which is verified by the in-depth experimental study and simulated calculations including the electron paramagnetic resonance(EPR)analysis,free radical quenching experiments,charge density distribution,and simulated built-in electric field formation at the interface,which acts as driving force to promote the separation of photoinduced electrons and holes.Finally,the photocatalytic mechanism of S-scheme photogenerated carrier migration for the Cu_(2)WS_(4)/MoS_(2) catalyst is revealed based on the systematic experimental techniques and simulated calculations,accounting for its superior photocatalytic oxidation and reduction activities.This study provides inspiring implications to develop high-efficient S-scheme photocatalytic systems for versatile applications in solarenergy conversion.
基金financially supported by the Natural Science Foundation of Hainan Province (No. 521RC495)Key Research and Development Project of Hainan Province (Nos. ZDYF2020037 and ZDYF2020207)+2 种基金the National Natural Science Foundation of China (Nos. 6210031211 and 21805104)Innovative Research Projects for Graduate Students of Hainan Province (No. Hyb2020-05)the Start-Up Research Foundation of Hainan University (Nos. KYQD(ZR)-20008, 20082, 20083, 20084, 21065)
文摘Inexpensive,safe,and efficient conversion of solar energy to hydrogen from water splitting requires the development of effective and durable photocatalysts.Cu_(2)ZnSnS_(4)(CZTS),the emerging quaternary chalcogenide material for solar energy conversion,possesses many advantages,such as narrow direct band gap(1.5 eV),nontoxic,earth-abundance,and low melting point.Currently,CZTS-based photocatalysts have been extensively investigated for their application as an active photocatalyst in hydrogen evolution from water splitting,while the performance is still highly needed to be improved for the practical applications.In this review,first,the crystal and band structure properties of CZTS are briefly introduced,and afterward,the basic principle of photocatalytic hydrogen evolution from water splitting is discussed.Subsequently,the performance and status of bare CZTS,the combination of CZTS and co-catalysts,and CZTSbased heterojunction photocatalysts for hydrogen evolution are reviewed and discussed in detail.Finally,the issues and challenges currently encountered in the application of CZTS and their possible solutions for developing advanced CZTS photocatalysts are provided.
