摘要
以CuCl_(2)、NH_(2)-MIL-125(Ti)和尿素为前驱物,通过煅烧法制备了不同Cu掺杂量的二氧化钛/聚合氮化碳(PCN)异质结(CuTiCN)。其中3CuTiCN光催化还原CO_(2)性能最优,在可见光下CO的产生速率可达735µmol/(g·h),分别是纯PCN和TiO_(2)/PCN异质结的9倍和3倍。利用X射线衍射(XRD)、傅里叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)、X射线光电子能谱(XPS)、氮气物理吸附、紫外可见漫反射光谱、光致发光谱(PL)等手段对光催化剂的组成、结构和光电化学性质进行了表征。研究发现,Cu掺杂和异质结的构建增强了可见光吸收,增大了材料的比表面积,提高了光生载流子的分离和传递效率。根据带隙数据和莫特-肖特基曲线得到了异质结的能带结构,并提出了Cu掺杂TiO_(2)/PCN异质结光催化还原CO_(2)的机理。
TiO_(2)/PCN heterojunctions(CuTiCN)with different Cu doping contents were prepared by calcination methods us‐ing CuCl_(2),NH_(2)-MIL-125(Ti)and urea as precursors.The 3CuTiCN photocatalyst exhibited the best photocatalytic CO_(2) re‐duction performance with CO evolution rate of 735µmol/(g·h),which was 9 and 3 times of the PCN and TiO_(2)/PCN hetero‐junction,respectively.The composition,structure and photoelectrochemical properties of the photocatalysts were character‐ized by X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),scanning electron microscopy(SEM),X-ray photoelectron spectroscopy(XPS),nitrogen physical adsorption,UV-Vis-DRS spectra,PL spectra,and etc.It was found that Cu doping and construction of heterojunction enhanced the visible light absorption,increased the specific surface area and promoted the separation and transfer efficiency of photogenerated carriers.Furthermore,the band structure of the heterojunction was obtained based on the band gap data and Mott-Schottky plots,and the photocatalytic mechanism of CO_(2) reduction over Cu-doped TiO_(2)/PCN heterojunction was proposed.
作者
赵炎
郝雪薇
时海南
李佳慧
李克艳
郭新闻
ZHAO Yan;HAO Xuewei;SHI Hainan;LI Jiahui;LI Keyan;GUO Xinwen(State Key Laboratory of Fine Chemicals,Frontier Science Center for Smart Materials,School of Chemical Engineering,Dalian University of Technology,Dalian 116024,China)
出处
《无机盐工业》
CAS
CSCD
北大核心
2023年第8期21-27,共7页
Inorganic Chemicals Industry
基金
辽宁省自然科学基金项目(2022-MS-131)
中央高校基本科研业务费专项资金资助项目(DUT22LAB602)。
关键词
光催化
二氧化碳还原
聚合氮化碳
CU掺杂
异质结
photocatalysis
CO_(2)reduction
polymeric carbon nitride
Cu doping
heterojunction
