三元Ho3+-TiO2/Bi等离子体复合纤维制备及其可见光催化产氢性能

Preparation of Ternary Ho3+-TiO2/Bi Plasmonic Composite Fibers for Photocatalytic H2 Production under Visible Light Irradiation

以电纺Ho 3+-TiO 2纳米纤维为基质,葡萄糖酸钠为还原剂,采用水热法制备Ho 3+-TiO 2/Bi等离子体复合纤维光催化剂。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、透射电子显微镜(TEM)、X射线光电子能谱(XPS)、紫外可见漫反射光谱(UV-Vis DRS)和瞬时光电流(IP)等分析测试手段对样品的物相、形貌和光电性能等进行表征。以三乙醇胺为电子给体,研究了Ho 3+-TiO 2/Bi光催化分解水产氢的反应过程。结果表明:在水热过程中,Bi 3+被葡萄糖酸钠还原成单质Bi纳米颗粒,复合在Ho 3+-TiO 2纳米纤维表面形成肖特基结。金属Bi通过局域表面等离子体共振效应结合稀土元素丰富的能级结构和4 f电子跃迁特性,对TiO 2进行双重修饰改性,有效提高了TiO 2的光催化活性和稳定性,可见光下产氢速率最大为43.6μmol/(g·h)。

Ternary Ho 3+-TiO 2/Bi plasmonic composite fibers were prepared via hydrothermal method employing electrospun Ho 3+-TiO 2 nanofibers as the substrate.The composition,morphology and photoelectric properties of the composite fibers were characterized by X-ray diffraction(XRD),X-ray photoelectric spectroscopy(XPS),scanning electron microscopy(SEM),transmission electron microscopy(TEM),ultraviolet-visible diffuse reflection spectrum(UV-Vis DRS)and instantaneous photocurrent.The photocatalytic water splitting for hydrogen evolution was investigated over Ho 3+-TiO 2/Bi plasmonic composite fibers with triethanolamine as the donor residue.The results showed that Bi nanoparticles formed via reduction of Bi 3+by sodium gluconate during hydrothermal process,meanwhile the heterojunction grew on the Ho 3+-TiO 2 nanofibers surface.The enhanced photocatalytic activity of the Ho 3+-TiO 2/Bi plasmonic composites fibers can be further improved,which was mainly attributed to the formation of high-quality heterojunctions between Bi and rare earth Ho 3+doped titanium dioxide.Modification of TiO 2 nanofibers effectively improved the photocatalytic activity and stability of the samples under visible light.The highest hydrogen production rate was 43.6μmol/(g·h).