质子化g-C3N4/β-SiC复合材料的制备及光催化降解茜素红性能  

Preparation of Protonated g-C3N4/β-SiC Composites and Photocatalytic Degradation of Alizarin Red S

作　　者：吴之强[1] 刘万毅[1] 王刚 蔡威 岳晓菲 詹海鹃 毕淑娴[1] 孟哲[1] 马保军[1] WU Zhiqiang;LIU Wanyi;WANG Gang;CAI Wei;YUE Xiaofei;ZHAN Haijuan;BI Shuxian;MENG Zhe;MA Baojun(State Key Laboratory of High-efficiency Utilization of Coal and Green Chemical Engineering,National Demonstration Center for Experimental Chemistry Education,College of Chemistry and Chemical Engineering,Ningxia University,Yinchuan 750021,China)

机构地区：[1]宁夏大学化学化工学院省部共建煤炭高效利用与绿色化工国家重点实验室化学国家级实验教学示范中心

出　　处：《高等学校化学学报》2019年第10期2178-2185,共8页Chemical Journal of Chinese Universities

基　　金：宁夏国内一流学科建设项目(批准号:NXYLXK2017A04);西部地区建设“一流大学”重大创新项目(批准号:ZKZD2017003);国家自然科学基金(批准号:21862013)资助~~

摘　　要：分别采用热解法和溶胶-凝胶-碳热还原法合成了石墨相氮化碳(g-C3N4)和纳米级碳化硅(β-Si C),通过浸渍-热处理法将两者复合并通过浓盐酸质子化,分别制备了g-C3N4/β-Si C和质子化g-C3N4/β-Si C(P-g-C3N4/β-Si C)复合光催化剂.利用X射线衍射(XRD)、扫描电子显微镜(SEM)、高分辨透射电子显微镜(HRTEM)、傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)、紫外-可见漫反射光谱(UV-Vis-DRS)和光致发光光谱(PL)等对样品进行了表征.结果表明,P-g-C3N4/β-Si C复合材料的比表面积增大,光生电子-空穴对的复合几率降低,光催化性能明显提高.在光催化降解染料茜素红(ARS)研究中,样品的可见光催化活性顺序为P-g-C3N4/β-Si C>g-C3N4/β-Si C>P-g-C3N4>g-C3N4>β-Si C.其中P-g-C3N4/β-Si C在60 min内对ARS的降解效率高达99.9%,符合准一阶动力学模型,速率常数为0.0967 min-1,且循环使用9次后,光催化降解效率仍保持97.5%以上.Graphite phase carbonitride(g-C3N4)and silicon carbide(β-SiC)were synthesized by pyrolysis and sol-gel-carbothermic reduction method,respectively.Then,they were combined by the impregnation-heat treatment and protonated by concentrated hydrochloric acid to prepare g-C3N4/β-Si C and protonated g-C3N4/β-Si C(P-g-C3N4/β-Si C)composite photocatalysts.The samples were analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),high resolution transmission electron microscopy(HRTEM),Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS),UV-Vis diffuse reflectance spectroscopy(UV-Vis-DRS)and phototluminescence(PL)characterization.The results show that the P-gC3N4/β-Si C composite did not retain the lamellar morphology and its specific surface area is significantly increased.The UV-Vis-DRS and PL spectra indicate that the recombination probability of photogenerated electron-hole pairs is significantly reduced,and the band gap is significantly improved.At the same time,experiments revealed that the combination of g-C3N4andβ-Si C and protonation can have a positive effect on the effective separation of photogenerated electron-hole pairs.In addition,the catalysts were applied to photocatalytic degradation of alizarin red S(ARS).The results show that the order of visible light photocatalytic activity of the samples is P-g-C3N4/β-Si C>g-C3N4/β-Si C>P-g-C3N4>g-C3N4>β-Si C.The degradation efficiency of sample P-g-C3N4/β-Si C to ARS was up to 99.9%within 60 min,which accorded with the pseudo first-order kinetic model.The rate constant was 0.0967 min-1.After 9 times of cycle,the photocatalytic degradation efficiency of P-g-C3N4/β-SiC for ARS remained above 97.5%.

关 键 词：g-C3N4/β-SiC 质子化 光催化降解 高效循环 茜素红 

分 类 号：O644.1[理学—物理化学]