无模板剂的溶胶-水热法合成具有可见光响应的氮掺杂混晶 TiO2(锐钛矿/金红石/板钛矿)纳米棒束

Template-free Sol-hydrothermal Synthesis of a Nitrogen Doped Anatase/rutile/brookite TiO2 Nano-rod Bundle for Visible Light Driven Photocatalysis

摘要:

采用无模板剂的溶胶-水热法制备了具有可见光响应的N掺杂锐钛矿/金红石/板钛矿型TiO₂(N-TiO₂)纳米棒束,并利用X射线衍射(XRD)、透射电镜(TEM)、紫外-可见光漫反射光谱(UV-Vis DRS)、傅里叶变换红外光谱(FTIR)和X射线光电子能谱(XPS)等手段对获得的样品进行了表征。以甲基橙为模型反应物,评价了N-TiO₂纳米棒束的光催化活性。表征结果结合光催化活性评价结果显示,与P25-TiO₂相比,N掺杂、混晶及纳米棒束之间的协同作用是所制备的混晶N-TiO₂纳米棒束具有良好光催化活性的主要原因,并对混晶N-TiO₂纳米棒束光催化降解甲基橙的机理进行了探讨。

Abstract:

Nitrogen doped anatase/rutile/brookite titanium dioxide (N-TiO₂) regular nano-rod bundle photocatalyst for improving visible light photocatalytic activity was prepared through a template-free sol-hydrothermal method. The properties of the materials were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), ultraviolet-visible diffuse reflectance spectra (UV-Vis DRS), Fourier transform infrared (FTIR) spectroscopy and X-ray photoelectron spectroscopy (XPS). Photocatalytic degradation of methyl orange (MO) in an aqueous solution under visible light irradiation was used as a probe reaction to evaluate the photocatalytic activity of the mixed-phase N-TiO₂ nano-rod bundle. The results of characterization combined with photocatalytic activity of MO photodegradation showed that the synergistic effects among N doping, mixed-phase and nano-rod bundle structure were the main reason to improve photocatalytic activity of mixed-phase N-TiO₂ nano-rod bundle compared with P25-TiO₂. The possible mechanism of MO degradation by mixed phase N-TiO₂ nano-rod bundle photocatalyst was preliminarily discussed.