双Z型异质结BiOI/MoO_(3)/g-C_(3)N_(4)的构建及其光催化性能研究  

Construction of double Z-scheme heterojunction BiOI/MoO3/g-C_(3)N_(4)and its photocatalytic performance

作　　者：霍彦廷 舒庆[1] HUO Yanting;SHU Qing(Faculty of Materials Metallurgy and Chemistry,Jiangxi University of Science and Technology,Ganzhou 341000,Jiangxi,China)

机构地区：[1]江西理工大学材料冶金化学学部,江西赣州341000

出　　处：《有色金属科学与工程》2023年第1期74-85,共12页Nonferrous Metals Science and Engineering

基　　金：国家自然科学基金资助项目(21766009)。

摘　　要：通过简单的溶剂热法将半导体MoO_(3)、BiOI与g-C_(3)N_(4)复合,构建双Z型异质结BiOI(x)/MoO_(3)/g-C_(3)N_(4)(x=6.25%、12.50%、18.75%、25.00%,x为BiOI的质量分数)三元复合材料,从HRTEM结果可知样品出现了2种间距分别为0.28 nm和0.33 nm的晶格条纹,结合XRD表征结果可知分别属于BiOI(110)和MoO_(3)(021)晶面,且g-C_(3)N_(4)是非晶态物质,由此表明BiOI/MoO_(3)/g-C_(3)N_(4)复合材料成功复合。UV-Vis DRS分析表明复合样品的带隙变窄,光学响应范围增强,PL和光电化学测试表征说明异质结的存在有效延缓了电子和空穴的复合,在模拟太阳光条件下对染料甲基橙(MO)进行降解并研究其光催化活性,BiOI(18.75)/MoO_(3)/g-C_(3)N_(4)具有较优异的光催化性能和光学稳定性,120 min对30 mg/L MO的降解率达94%,是纯g-C_(3)N_(4)的3.6倍。ESR表征说明BiOI/MoO_(3)/g-C_(3)N_(4)光催化降解的主要活性物质组分为·OH和·O_(2)-,并通过计算BiOI、MoO_(3)和g-C_(3)N_(4)的价带和导带位置,表明3种物质是能带交错结构,推测出三元复合物形成双Z型异质结。BiOI/MoO_(3)/g-C_(3)N_(4)可作为一种有效应用于有机染料污染物降解的可见光响应催化剂,具有应用前景。Se miconductors MoO_(3),BiOI and g-C_(3)N_(4)were compounded by a simple solvent thermal method,and finally,the ternary composite of double Z-scheme heterojunction BiOI(x)/MoO_(3)/g-C_(3)N_(4)(x=6.25%,12.50%,18.75%,25.00%,x:mass percentage of BiOI)was constructed.From the HRTEM results,it can be seen that two types of lattice fringes with spacings of 0.28 nm and 0.33 nm appear in the sample.Combined with the XRD char acterization results,it could be seen that they respectively belong to BiOI(110)and MoO_(3)(021)crystal planes,which thus indicats that the BiOI/MoO_(3)/g-C_(3)N_(4)composite was successfully compounded,since g-C_(3)N_(4)is amorphous material.The results of UV-Vis DRS show the decreased band gap and greater optical response range of the composite samples.The PL and photoelectrochemical test characterizations illustrate that the presence of the heterojunction effectively delays the recombination of electrons and holes.The dye methyl orange(MO)was degraded under simulated sunlight conditions,and its photocatalytic activity was studied.BiOI(18.75)/MoO_(3)/g-C_(3)N_(4)had the best photocatalytic performance and optical stability,and the degradation rate of 30 mg/L MO was 94%for 120 min,which is 3.6 times that of pure g-C_(3)N_(4).The ESR characterization indicates that the main active material components for the photocatalytic degradation of BiOI/MoO_(3)/g-C_(3)N_(4)were·OH and·O_(2)-.By calculating the positions of the valence and conduction bands of BiOI,MoO_(3)and g-C_(3)N_(4),it is shown that the three substances are band staggered structures,suggesting that the ternary complex forms a double Z-scheme heterojunction.BiOI/MoO_(3)/g-C_(3)N_(4)may serve as an effective visible light-responsive catalyst for the degradation of organic dye pollutants,with promising applications.

关 键 词：MOO3 BiOI g-C_(3)N_(4) 光催化性能 双Z型异质结光催化剂 

分 类 号：O643.3[理学—物理化学]