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

以电纺Ho³⁺-TiO₂纳米纤维为基质,葡萄糖酸钠为还原剂,采用水热法制备Ho³⁺-TiO₂/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Ho³⁺-TiO₂/Bi光催化分解水产氢的反应过程。 结果表明:在水热过程中,Bi³⁺被葡萄糖酸钠还原成单质Bi纳米颗粒,复合在Ho³⁺-TiO₂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4f电子跃迁特性,对TiO₂进行双重修饰改性,有效提高了TiO₂的光催化活性和稳定性,可见光下产氢速率最大为43.6 μmol/(g·h)。

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

Ternary Ho³⁺-TiO₂/Bi plasmonic composite fibers were prepared via hydrothermal method employing electrospun Ho³⁺-TiO₂ 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 Ho³⁺-TiO₂/Bi plasmonic composite fibers with triethanolamine as the donor residue. The results showed that Bi nanoparticles formed via reduction of Bi³⁺ by sodium gluconate during hydrothermal process, meanwhile the heterojunction grew on the Ho³⁺-TiO₂ nanofibers surface. The enhanced photocatalytic activity of the Ho³⁺-TiO₂/Bi plasmonic composites fibers can be further improved, which was mainly attributed to the formation of high-quality heterojunctions between Bi and rare earth Ho³⁺ doped titanium dioxide. Modification of TiO₂ nanofibers effectively improved the photocatalytic activity and stability of the samples under visible light. The highest hydrogen production rate was 43.6 μmol/(g·h).