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
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.