摘要
通过负载法成功制备了g-C_(3)N_(4)/BiVO_(4)异质结,采用XRD、SEM、BET、UV-Vis DRS、Mott Schottky、SPV等技术对样品的结构与性质进行分析,以光催化降解RhB和光催化还原CO_(2)评价其光催化活性。结果表明,g-C_(3)N_(4)和BiVO_(4)能带结构匹配,能够组成“Z”型异质结,并有效提高光生载流子的分离效率,同时保留g-C_(3)N_(4)导带电子较强的还原性和BiVO_(4)价带空穴较强的氧化性,最终提高光催化活性,其中当g-C_(3)N_(4)的负载量为3%时,样品展现了最佳的光催化活性,在光催化降解RhB实验中,经过180min光照后,降解率达到95.3%,反应速率常数达到0.0166min^(-1);而在光催化还原CO_(2)的实验中,经过4h光照后,CO和O_(2)的产量达到70.2μmol·g^(-1)和45.6μmol·g^(-1),较纯g-C_(3)N_(4)和BiVO_(4)均明显提高。
g-C_(3)N_(4)/BiVO_(4)heterojunction was successfully prepared through loading method.The structure and properties of as-synthesized samples were analyzed using XRD,SEM,BET,UV-Vis DRS,Mott Schottky,SPV and other techniques.Its photocatalytic activity was evaluated by photocatalytic degradation of RhB and photocatalytic reduction of CO_(2).The experiment results showed that the energy band structures of g-C_(3)N_(4)and BiVO_(4)conform to"Z"type heterojunction,and can effectively improve the separation efficiency of photogenerated carriers,at the same time,the strong reducibility of g-C_(3)N_(4)conduction band electrons and the strong oxidation of BiVO_(4)valence band holes are preserved,these characteristic ultimately improve its photocatalytic activity,the sample with 3%g-C_(3)N_(4)loading amount exhibits the most excellent photocatalytic activity.In the experiment of photocatalytic degradation of RhB,the degradation rate reaches 95.3%after 180 minutes of illumination and the reaction rate constant reaches 0.0166min^(-1);In the experiment of photocatalytic reduction of CO_(2),the yields of CO and O_(2) reached 70.2μmol·g^(-1)and 45.6μmol·g^(-1)after 4 hours of illumination,which are significantly higher than that of pure g-C_(3)N_(4)and BiVO_(4).
作者
尹香琴
YIN Xiang-qin(Cangzhou Ecological Environment Bureau Hejian Branch,Cangzhou 062450,China)
出处
《化学工程师》
CAS
2024年第4期38-43,共6页
Chemical Engineer
基金
河北省科技计划项目(2022B020321016)。