Gd-N共掺杂SrTiO3/TiO2复合纳米纤维制备及光催化性能

以静电纺丝技术制备的TiO_2纳米纤维为基质和反应物,结合一步水热法制得Gd-N共掺杂SrTiO_3/TiO_2复合纳米纤维光催化剂。利用X射线衍射(XRD)、扫描电子显微镜(SEM)、高分辨透射电镜(HRTEM)、X射线光电子能谱(XPS)、紫外-可见漫反射(UV-Vis DRS)和荧光光谱(PL)等方法对其微观结构、形貌和光学性能进行表征。结果表明:SrTiO_3和TiO_2形成异质结能够使光生电子和空穴得到很好的分离,而Gd-N共掺杂产生新带隙,可以拓宽光谱响应范围至可见光区,并引起晶格缺陷,成为光生电子-空穴对的浅势捕获阱。Gd-N共掺杂与异质结的协同作用有效提高了SrTiO_3/TiO_2复合纳米纤维的可见光催化活性。

Preparation and Photocatalytic Activity of Gd-N Co-doped SrTiO3/TiO2 Composite Nanofibers

Gd and N co-doped SrTiO₃/TiO₂ composite nanofibers were prepared via one step hydrothermal synthesis growth of SrTiO₃ nanostructures using electrospun anatase TiO₂ nanofibers as both substance and reactant. The phase composition, microstructure, morphology and optical properties of the sample were characterized by X-ray diffraction (XRD), scanning electron mictoscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS) and photoluminescence spectroscopy (PL). The results indicated that the heterostructure formed by SrTiO₃ and TiO₂, plays an important role in the suppression of electron-hole recombination and improves the photocatalytic performance of TiO₂ nanofibers. The excellent visible light photocatalytic activity of this substance may be due to the generation of a new band gap that enables the catalyst to absorb visible light and results in the lattice defects which acts as a recombination center of photoinduced electrons and holes. The synergistic effect of Gd-N co-doping and heterojunction could effectively improve the visible-light photocatalytic activity of SrTiO₃/TiO₂ composite nanofibers.