CdS/g-C_(3)N_(4)复合光催化剂的合成及催化机理研究  

Study on synthesis and catalytic mechanism of CdS/g-C_(3)N_(4)composite photocatalyst

作　　者：李子罕 张佳琦 李世卓 李欣雨 刘少卓 王一豪 郝玉翠[1] 刘剑[1] 李彦华 LI Zihan;ZHANG Jiaqi;LI Shizhuo;LI Xinyu;LIU Shaozhuo;WANG Yihao;HAO Yucui;LIU Jian;LI Yanhua(School of New Materials and Chemical Engineering,Tangshan University,Tangshan 063099,China;Jijianlian(Tangshan)Environmental Testing Technology Co.,Ltd.,Tangshan 063010,China)

机构地区：[1]唐山学院新材料与化学工程学院,河北唐山063099 [2]冀检联(唐山)环境检测技术有限公司,河北唐山063010

出　　处：《无机盐工业》2025年第3期124-132,共9页Inorganic Chemicals Industry

基　　金：唐山市科技计划项目(22130218G);校企合作技术研发项目(JJL202401)。

摘　　要：以三聚氰胺为原料,通过烧结-超声两步法制备了g-C_(3)N_(4)黄色粉末;再以所制备g-C_(3)N_(4)、硫化钠和乙酸镉为原料,采用水热法成功制备出了CdS纳米颗粒包裹g-C_(3)N_(4)片层结构的CdS/g-C_(3)N_(4)复合光催化剂。采用X射线衍射(XRD)、场发射扫描电子显微镜(FE-SEM)、紫外可见漫反射(UV-Vis-DRS)、X射线荧光光谱(XRF)、X射线光电子能谱(XPS)等对CdS、g-C_(3)N_(4)和CdS/g-C_(3)N_(4)复合光催化剂进行物相组成、微观形貌及物化性能表征。测试结果表明:所制备CdS的微观形貌为纳米颗粒结构,g-C_(3)N_(4)为片层结构;在CdS/g-C_(3)N_(4)复合材料中,g-C_(3)N_(4)片层周围包裹着不规则颗粒CdS,二者紧密结合成了一个整体的复合粉体颗粒。以罗丹明B为目标降解物,以氙灯模拟可见光光源,测试CdS、g-C_(3)N_(4)和CdS/g-C_(3)N_(4)复合材料的光催化性能。结果表明,CdS/g-C_(3)N_(4)复合光催化剂具有良好的光催化性能,当CdS和g-C_(3)N_(4)质量比为1∶5时,复合材料的光催化活性要明显强于单一CdS或g-C_(3)N_(4)样品的催化活性,光照40 min后罗丹明B的降解率可达93.7%,降解过程符合一级动力学方程,其降解速率为6.6×10^(-2) min^(-1)。通过捕获实验分析得到光降解罗丹明B的主要活性基团为羟基自由基,基于机理和降解结果分析,推测CdS和g-C_(3)N_(4)之间应该是形成了Z型异质结。g-C_(3)N_(4)yellow powder was prepared by sintering and ultrasonic two-step method using melamine as raw material.Then the CdS/g-C_(3)N_(4)composite photocatalyst with CdS nanoparticles coated to g-C_(3)N_(4)layer structure was successfully prepared by hydrothermal method using the prepared g-C_(3)N_(4),sodium sulfide and cadmium acetate as raw materials.The phase composition,microstructure,physical and chemical properties of CdS,g-C_(3)N_(4)and CdS/g-C_(3)N_(4)composite photocatalysts were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FE-SEM),ultraviolet-visibleinfrared diffuse reflectance spectroscopy(UV-Vis-DRS),X-ray fluorescence spectroscopy(XRF)and X-ray photoelectron spectroscopy(XPS).The test results showed that the microstructure of prepared CdS was nanoparticle and g-C_(3)N_(4)was lamellar structure.In the CdS/g-C_(3)N_(4)composite materials,the g-C_(3)N_(4)layer was surrounded by irregular CdS particles,g-C_(3)N_(4)and CdS were closely combined into a whole composite powder particles.The photocatalytic properties of CdS,g-C_(3)N_(4)and CdS/g-C_(3)N_(4)composites were tested using Rhodamine B as target degradation material and xenon lamp as light source.The results showed that CdS/g-C_(3)N_(4)composite photocatalyst had good photocatalytic performance,when the mass ratio of CdS to g-C_(3)N_(4)was 1∶5,the photocatalytic activity of the composite was significantly stronger than that of single CdS or g-C_(3)N_(4)sample.The degradation rate of Rhodanine B reached 93.7%after 40 min illumination,which was in line with the first-order kinetic equation,and the degradation rate was 6.6×10^(-2) min^(-1).The main active free radical for photodegradation of Rhodamine B was hydroxyl free radical.Based on the mechanism and degradation results,it was speculated that Z-type heterojunction should be formed between CdS and g-C_(3)N_(4).

关 键 词：CdS/g-C_(3)N_(4) 光催化 水热法 合成 催化机理 

分 类 号：TQ127.1[化学工程—无机化工]