Ho掺杂对纳米TiO_2晶体结构和光催化性能的影响

INFLUENCE OF Ho DOPING ON THE CRYSTAL STRUCTURE AND PHOTOCATALYTIC ACTIVITY OF TiO_2

采用溶胶-凝胶法制备了纯的和Ho掺杂的TiO2纳米粒子,对样品进行了X射线衍射分析,并以甲基橙的光催化降解研究了样品的光催化性能。结果发现:Ho的掺杂不但抑制了TiO2粒径的长大,细化了晶粒,而且引起了晶格的畸变和膨胀。Ho的掺杂有抑制TiO2晶型转变的作用。适量Ho的掺杂可提高TiO2的光催化性能,在所进行试验的条件下,最佳掺杂摩尔分数为0.3%。煅烧温度为600℃时,掺杂和未掺杂的TiO2光催化性能均最佳,且Ho掺杂的TiO2光催化性能高于未掺杂的TiO2。

Pure and Ho-doped TiO2 nanoparticles were prepared by the sol-gel method and characterized with X-ray diffraction, and their photocatalytic activity was studied by photocatalytic oxidation of methyl orange. It was found that Ho doping not only restrained the increase of the grain size of TiO2, but also led to distortion and expansion of crystal lattice. Ho doping inhibites the phase transformation of TiO2 from anatase to futile. Doping with the appropriate Ho content can improve the photocatalytic activity of TiO2. In the experimental conditions used, the optimal photocatalytic activity for all the prepared samples is reached when the Ho doping molar fraction was 0.3%. The photocatalytic activity of both Ho-doped and un-doped TiO2 is optimal when the samples were calcined at 600℃, and Ho-doped TiO2 is superior to un-doped TiO2.