Cu/Ag-TiO₂复合材料的制备及其光催化CO₂还原性能研究  

Fabrication and Photocata-lytic CO2 Reduction Performances of Cu/Ag-TiO2 Composites

作　　者：胡景茹 陈巍 童鑫雨 程刚 

机构地区：[1]武汉工程大学化学与环境工程学院,湖北 武汉

出　　处：《材料科学》2023年第11期968-976,共9页Material Sciences

摘　　要：通过硬模板法在多元醇反应体系中经溶剂热处理得到SiO2@Ti-glycerol前驱体,经NaOH蚀刻SiO2得到富孔锐钛矿型TiO2,通过NaBH4还原方法将金属颗粒(Cu, Ag)沉积在其表面而成功制备了Cu/TiO2及Ag/TiO2复合材料。通过X射线粉末衍射(XRD)、X射线光电子能谱(XPS)、扫描电子显微镜(SEM)、紫外–可见漫反射光谱(UV-DRS)等表征手段对所制备材料的组成与结构进行确认。光催化CO2还原实验结果表明,Cu、Ag的引入提升了单一TiO2光催化CO2还原活性。其中,复合材料Cu/TiO2和Ag/TiO2光催化CO2还原为CH4的产量分别达到2.52与9.41 μmol•g−1•h−1,为单一TiO2的5.5和20.5倍。并且Ag/TiO2提升了CO的产率。光/电化学测试结果表明金属的引入改变了半导体能带结构,形成了肖特基结,促进了光生电荷的分离,为CO2还原过程提供更多的电子,进而增强了光催化还原效率。The SiO2@Ti-glycerol precursor was obtained by solvothermal treatment in polyol reaction system by hard template method. Pores-enriched anatase TiO2 was obtained by etching SiO2 with NaOH. Cu/TiO2 and Ag/TiO2 composites were successfully prepared through deposition of metal particles (Cu and Ag) by NaBH4 reduction method. The composition and structure of the prepared materials were confirmed by X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM) and ultraviolet-visible diffuse reflection spectroscopy (UV-DRS). The results of photocatalytic CO2 reduction showed that the introduction of Cu and Ag promoted CO2 reduction. The production of Cu/TiO2 and Ag/TiO2 photocatalyzed CO2 reduction of CH4 reached 2.52 and 9.41 μmol•g−1•h−1, respectively, which were 5.5 and 20.5 times that of single TiO2. Moreover, Ag/TiO2 improved the CO yield. The photoelectrochemical test results suggested that the introduction of metal could change the semiconductor band structure, form a Schottky junction, promote charges separation, and provide more electrons for the CO2 reduction process, thus enhancing the photocatalytic reduction efficiency.

关 键 词：金属–二氧化钛复合材料 光催化CO2还原 肖特基结 电荷分离 

分 类 号：O64[理学—物理化学]