摘要
采用溶胶—凝胶法制备了掺杂不同量Fe,N的TiO2/SiO2复合纳米粒子。通过红外光谱、X射线衍射、透射电子显微镜等对制备的样品的结构和形貌进行表征。以甲基橙水溶液的光催化降解为模拟反应,在紫外光照射下评价了样品的光催化活性。结果表明:Fe,N共掺杂TiO2/SiO2为核壳结构,SiO2核与TiO2壳间形成了Ti—O—Si键。由于金属Fe3+离子抑制光生载流子的复合,非金属N降低了TiO2/SiO2的带隙能,Fe,N共掺杂的协同作用使复合TiO2/SiO2具有更好的光催化性能。共掺杂0.05%Fe及0.05%N的TiO2/SiO2复合光催化粒子的催化活性最高,光照1h后对甲基橙的降解率提高到52%。
The composite nanoparticles of TiO2/SiO2 with different mole fractions of Fe,N were prepared by a sol gel method.The structure and morphology of the obtained samples were characterized by Fourier transform infrared spectroscopy,X-ray diffraction and transmission electron microscopy,respectively.The photocatalytic activity was evaluated via the degradation of methyl orange solution under UV light irradiation.The resuhs show that the TiO2/SiO2 co doped with iron and nitrogen appears a core-shell structure.The phase transition of TiO2 at a high temperature was affected due to the formation of the Ti-O-Si bond.The higher UV-visible light photocatalytic activity of co doped TiO2 is attributed to the partial N atoms,leading to the decrease of the band gap and the absorption edge of TiO2/SiO2 to be shifted into the lower-energy region.The doping of Fe3＋ restrains a recombination rate of photogenerated electrons and holes.The doping can favor the improvement of the photocatalysis of TiO2/SiO2 co doped with iron and nitrogen under UV light irradiation.The TiO2/SiO2 composite particles co doped with 0.05％ Fe and 0.05％ N has the optimum catalytic activity,and the degradation rate of methyl orange increases to 52％ after UV light irradiation for 1 h.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2014年第6期802-807,共6页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(21067010)
宁夏高校科学研究基金(2012)资助项目
