Constructing step-scheme(S-scheme)heterojunctions can considerably facilitate separation and transfer of photocarriers,as well as promote strong redox ability.The interface resistance of heterojunctions immediately af...Constructing step-scheme(S-scheme)heterojunctions can considerably facilitate separation and transfer of photocarriers,as well as promote strong redox ability.The interface resistance of heterojunctions immediately affects photocarrier separation and determines the photocatalytic activity.Herein,we constructed a novel Bi OBr/Ni_(2)P/g-C_(3)N_(4) heterojunction using Ni_(2)P as a novel electron bridge to reduce the interfacial resistance of photocarriers between Bi OBr and g-C3N4.The as-prepared 10% BiOBr/Ni2P/g-C_(3)N_(4) sample exhibited outstanding visible-light photocatalytic performance for methyl orange and rhodamine B removal,with degradation efficiencies of 91.4% and 98.9%,respectively.The excellent photocatalytic activity of Bi OBr/Ni_(2)P/g-C_(3)N_(4) was mainly attributed to the synergistic effects of the Ni2P cocatalyst and S-scheme heterojunction,which not only reduced the interface resistance but also retained the strong redox potential of the photocarriers.In addition,the formation of the S-scheme system was supported by active oxygen species investigation,current-voltage curves,and density functional theory calculations.This work provides a guideline for the design of highly efficient S-scheme photocatalysts with transition metal phosphates as electron bridges to improve photocarriers separation.展开更多
Construction of multi-channels of photo-carrier migration in photocatalysts is favor to boost conversion efficiency of solar energy by promoting the charge separation and transfer.Herein,a ternary ZnIn_(2)S_(4)/g-C_(3...Construction of multi-channels of photo-carrier migration in photocatalysts is favor to boost conversion efficiency of solar energy by promoting the charge separation and transfer.Herein,a ternary ZnIn_(2)S_(4)/g-C_(3)N_(4)/Ti_(3)C_(2) MXene hybrid composed of S-scheme junction integrated Schottky-junction was fabricated using a simple hydrothermal approach.All the components(g-C_(3)N_(4),ZnIn_(2)S_(4) and Ti_(3)C_(2) MXene)demonstrated two-dimensional(2D)nanosheets structure,leading to the formation of a 2D/2D/2D sandwich-like structure with intimate large interface for carrier migration.Furthermore,the photogenerated carriers on the g-C_(3)N_(4) possessed dual transfer channels,including one route in S-scheme transfer mode between the g-C_(3)N_(4) and ZnIn_(2)S_(4) and the other route in Schottky-junction between g-C_(3)N_(4) and Ti_(3)C_(2) MXene.Consequently,a highly efficient carrier separation and transport was realized in the ZnIn_(2)S_(4)/g-C_(3)N_(4)/Ti_(3)C_(2) MXene heterojunction.This ternary sample exhibited wide light response from 200 to 1400 nm and excellent photocatalytic H_(2) evolution of 2452.1μmol∙g^(–1)∙h^(–1),which was 200,3,1.5 and 1.6 times of g-C_(3)N_(4),ZnIn_(2)S_(4),ZnIn_(2)S_(4)/Ti_(3)C_(2) MXene and g-C_(3)N_(4)/ZnIn_(2)S_(4) binary composites.This work offers a paradigm for the rational construction of multi-electron pathways to regulate the charge separation and migration via the introduction of dual-junctions in catalytic system.展开更多
基金The financial supports from Nation-al Natural Science Foundation of China (Grant No. 41763020)Natural Science Foundation of Jiangxi Province (GrantsNo.20171BAB206008, 20202BABL214040)Foundation of Jiangxi Educational Commission (Grant No. GJJ180596)。
文摘Constructing step-scheme(S-scheme)heterojunctions can considerably facilitate separation and transfer of photocarriers,as well as promote strong redox ability.The interface resistance of heterojunctions immediately affects photocarrier separation and determines the photocatalytic activity.Herein,we constructed a novel Bi OBr/Ni_(2)P/g-C_(3)N_(4) heterojunction using Ni_(2)P as a novel electron bridge to reduce the interfacial resistance of photocarriers between Bi OBr and g-C3N4.The as-prepared 10% BiOBr/Ni2P/g-C_(3)N_(4) sample exhibited outstanding visible-light photocatalytic performance for methyl orange and rhodamine B removal,with degradation efficiencies of 91.4% and 98.9%,respectively.The excellent photocatalytic activity of Bi OBr/Ni_(2)P/g-C_(3)N_(4) was mainly attributed to the synergistic effects of the Ni2P cocatalyst and S-scheme heterojunction,which not only reduced the interface resistance but also retained the strong redox potential of the photocarriers.In addition,the formation of the S-scheme system was supported by active oxygen species investigation,current-voltage curves,and density functional theory calculations.This work provides a guideline for the design of highly efficient S-scheme photocatalysts with transition metal phosphates as electron bridges to improve photocarriers separation.
文摘Construction of multi-channels of photo-carrier migration in photocatalysts is favor to boost conversion efficiency of solar energy by promoting the charge separation and transfer.Herein,a ternary ZnIn_(2)S_(4)/g-C_(3)N_(4)/Ti_(3)C_(2) MXene hybrid composed of S-scheme junction integrated Schottky-junction was fabricated using a simple hydrothermal approach.All the components(g-C_(3)N_(4),ZnIn_(2)S_(4) and Ti_(3)C_(2) MXene)demonstrated two-dimensional(2D)nanosheets structure,leading to the formation of a 2D/2D/2D sandwich-like structure with intimate large interface for carrier migration.Furthermore,the photogenerated carriers on the g-C_(3)N_(4) possessed dual transfer channels,including one route in S-scheme transfer mode between the g-C_(3)N_(4) and ZnIn_(2)S_(4) and the other route in Schottky-junction between g-C_(3)N_(4) and Ti_(3)C_(2) MXene.Consequently,a highly efficient carrier separation and transport was realized in the ZnIn_(2)S_(4)/g-C_(3)N_(4)/Ti_(3)C_(2) MXene heterojunction.This ternary sample exhibited wide light response from 200 to 1400 nm and excellent photocatalytic H_(2) evolution of 2452.1μmol∙g^(–1)∙h^(–1),which was 200,3,1.5 and 1.6 times of g-C_(3)N_(4),ZnIn_(2)S_(4),ZnIn_(2)S_(4)/Ti_(3)C_(2) MXene and g-C_(3)N_(4)/ZnIn_(2)S_(4) binary composites.This work offers a paradigm for the rational construction of multi-electron pathways to regulate the charge separation and migration via the introduction of dual-junctions in catalytic system.
基金supported by Shanghai Pujiang Program(21PJ1400400)Shanghai Municipal Science and Technology Commission(22511103900)+1 种基金the Fundamental Research Funds for the Central Universities(2232023A-02)the National Natural Science Foundation of China(22173017).