利用HCl与Na Bi O3反应原位制备了结构可控的Bi OCl/Na Bi O3复合光催化材料.通过X射线粉末衍射(XRD)、紫外-可见漫反射光谱(UV-Vis-DRS)和扫描电子显微镜(SEM)等技术对其晶相组成、光吸收特性和表面形貌进行了表征,并评价了样品在可见...利用HCl与Na Bi O3反应原位制备了结构可控的Bi OCl/Na Bi O3复合光催化材料.通过X射线粉末衍射(XRD)、紫外-可见漫反射光谱(UV-Vis-DRS)和扫描电子显微镜(SEM)等技术对其晶相组成、光吸收特性和表面形貌进行了表征,并评价了样品在可见光和紫外光下的光催化性能.结果表明,尽管Bi OCl几乎没有可见光活性,但27.4%Bi OCl/Na Bi O3在可见光下却表现出明显高于纯Bi OCl和Na Bi O3的光催化活性.由于紫外光照可以有效激发Bi OCl,所有组成的复合Bi OCl/Na Bi O3都显示出高于纯Bi OCl和Na Bi O3的光催化活性,其中47.6%Bi OCl/Na Bi O3具有最大光催化活性.研究了加入不同活性物种的捕获剂对光催化效率的影响,结合荧光实验结果和样品能带结构推测了复合材料光催化过程中光生载流子的传输行为.结果表明,Bi OCl/Na Bi O3催化活性增强主要归结于2种材料之间形成了有效的异质结构,其内建电场能够促进光生载流子的传输和分离;羟基自由基在光催化降解过程中是主要的活性物种.展开更多
以五水硝酸铋、溴化钾和三聚氰胺为原料,采用溶剂热法制备了摩尔比不同的BiOBr/g-C_3N_4复合光催化剂,并进行了XRD、SEM和DRS表征分析。以50 W LED紫光灯为光源,采用罗丹明B为目标降解物考察了制备样品的光催化性能。结果表明:摩尔比为1...以五水硝酸铋、溴化钾和三聚氰胺为原料,采用溶剂热法制备了摩尔比不同的BiOBr/g-C_3N_4复合光催化剂,并进行了XRD、SEM和DRS表征分析。以50 W LED紫光灯为光源,采用罗丹明B为目标降解物考察了制备样品的光催化性能。结果表明:摩尔比为1∶1的BiOBr/g-C_3N_4复合光催化剂的具有最优的光催化性能。机理实验结果表明:超氧自由基(O_2·^-)和空穴(h+)为BiOBr/g-C_3N_4复合光催化剂光催化过程最为主要的活性物种。展开更多
The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In...The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In this study,2D/2D BiOBr/g‐C_(3)N_(4)heterojunctions were successfully obtained by a convenient in situ self‐assembly route.Under simulated sunlight irradiation,99%of RhB(10 mg·L–1,100 mL)was efficiently degraded by 1.5‐BiOBr/g‐C_(3)N_(4)within 30 min,which is better than the performance of both BiOBr and g‐C_(3)N_(4),and it has superior stability.In addition,the composite also exhibits enhanced photocatalytic activity for H2 production.The enhanced activity can be attributed to the intimate interface contact,the larger surface area,and the highly efficient separation of photoinduced electron–hole pairs.Based on the experimental results,a novel S‐scheme model was proposed to illuminate the transfer process of charge carriers.This study presents a simple way to develop novel step‐scheme photocatalysts for environmental and related applications.展开更多
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
文摘利用HCl与Na Bi O3反应原位制备了结构可控的Bi OCl/Na Bi O3复合光催化材料.通过X射线粉末衍射(XRD)、紫外-可见漫反射光谱(UV-Vis-DRS)和扫描电子显微镜(SEM)等技术对其晶相组成、光吸收特性和表面形貌进行了表征,并评价了样品在可见光和紫外光下的光催化性能.结果表明,尽管Bi OCl几乎没有可见光活性,但27.4%Bi OCl/Na Bi O3在可见光下却表现出明显高于纯Bi OCl和Na Bi O3的光催化活性.由于紫外光照可以有效激发Bi OCl,所有组成的复合Bi OCl/Na Bi O3都显示出高于纯Bi OCl和Na Bi O3的光催化活性,其中47.6%Bi OCl/Na Bi O3具有最大光催化活性.研究了加入不同活性物种的捕获剂对光催化效率的影响,结合荧光实验结果和样品能带结构推测了复合材料光催化过程中光生载流子的传输行为.结果表明,Bi OCl/Na Bi O3催化活性增强主要归结于2种材料之间形成了有效的异质结构,其内建电场能够促进光生载流子的传输和分离;羟基自由基在光催化降解过程中是主要的活性物种.
基金supported by the National Natural Science Foundation of China(51602297)Fundamental Research Funds for the Central Universities(201612007)+1 种基金Postdoctoral Innovation Program of Shandong Province(201603043)the Major Research Project of Shandong Province(2016ZDJS11A04)
文摘以五水硝酸铋、溴化钾和三聚氰胺为原料,采用溶剂热法制备了摩尔比不同的BiOBr/g-C_3N_4复合光催化剂,并进行了XRD、SEM和DRS表征分析。以50 W LED紫光灯为光源,采用罗丹明B为目标降解物考察了制备样品的光催化性能。结果表明:摩尔比为1∶1的BiOBr/g-C_3N_4复合光催化剂的具有最优的光催化性能。机理实验结果表明:超氧自由基(O_2·^-)和空穴(h+)为BiOBr/g-C_3N_4复合光催化剂光催化过程最为主要的活性物种。
文摘The design and construction of heterojunction photocatalysts,which possess a staggered energy band structure and appropriate interfacial contact,is an effective way to achieve outstanding photocatalytic performance.In this study,2D/2D BiOBr/g‐C_(3)N_(4)heterojunctions were successfully obtained by a convenient in situ self‐assembly route.Under simulated sunlight irradiation,99%of RhB(10 mg·L–1,100 mL)was efficiently degraded by 1.5‐BiOBr/g‐C_(3)N_(4)within 30 min,which is better than the performance of both BiOBr and g‐C_(3)N_(4),and it has superior stability.In addition,the composite also exhibits enhanced photocatalytic activity for H2 production.The enhanced activity can be attributed to the intimate interface contact,the larger surface area,and the highly efficient separation of photoinduced electron–hole pairs.Based on the experimental results,a novel S‐scheme model was proposed to illuminate the transfer process of charge carriers.This study presents a simple way to develop novel step‐scheme photocatalysts for environmental and related applications.
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.
