氮镍共掺杂TiO2纳米管的制备及其光催化性能

摘要

TiO2 nanotubes were synthesized by typical hydrothermal method.In order to improve shape stability and visible light response the as-synthesized TiO2 nanotubes were modified by nitrogen doping in NH4C1 via hydro-solvo-thermal process and nickel doping in Ni(NO3)2 aqueous solution.The samples were characterized by X-ray diffraction (XRD),scanning electron microscope (SEM),X-ray photoelectron spectroscopy (XPS),UV-vis diffuse reflect spectroscope(UV-vis DRS) and photoluminescence spectrum (PL),etc.The photocatalytic performance of the nitrogen and nickel codoped TiO2 nanotubes was evaluated by the degradation model of methylene orange (MO) under visible light.The results show that the nitrogen doping by hydro-solvo-thermal treatment in NH4 Cl solution can improve thermal stability of tubular shape of the TiO3nanotubes.The synergistic effect between the doped nitrogen and nickel could enhance the visible light absorption and restrain the electron and hole recombination.The photocatalysts show higher photocatalytic activity when the dosage ratio of Ni/Ti is 0.3％.And the degradation of MO by the nitrogen and nickel codoped photocatalyst is 9.1％(21.2％) higher than that of nitrogen (nickel) individually doped.%为了制备在高温焙烧后能保持良好管形结构的可见光响应的,TiO2纳米管,通过NH4Cl水—溶剂热和Ni(NO3)2浸渍法对传统水热法合成的TiO2纳米管进行掺氮和掺镍改性.通过X射线衍射(XRD)、扫描电子显微镜(SEM)、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)等方法对样品进行了表征,并以甲基橙(MO)为光催化降解模型,考察了可见光下制备的样品的光催化性能.结果表明,NH4Cl水-溶剂热掺氮处理可提高TiO2纳米管的管状结构的热稳定性；氮镍共掺杂元素之间的协同作用增强了催化剂对可见光的吸收能力,并且能有效地抑制光生电子空穴的复合,Ni/Ti添加量为0.3％的催化剂具有较高的光催化活性.可见光照射210 min,氮镍共掺杂TiO2纳米管对MO的可见光降解率比单独氮和镍掺杂的TiO2分别提高了9.1％和21.2％.