铜掺杂纳米二氧化钛颗粒的相变研究

Phase transition process of Cu-doped TiO_2 nanoparticles

采用溶胶-凝胶法制备铜掺杂的纳米二氧化钛颗粒。应用X射线衍射(XRD)、透射电子显微镜(TEM)、扫描透射电子显微镜(STEM)、X射线光电子能谱(XPS)和紫外-可见分光光度计(UV-Vis)技术对纳米二氧化钛颗粒的物相组成、平均晶粒尺寸、微观结构、化学态及光吸收性能进行表征。结果表明:Cu掺杂抑制TiO_2的相变,在650℃时Cu的氧化物CuO在TiO_2颗粒表面出现,掺杂的Cu离子以Cu^+的形式存在。掺杂Cu的TiO_2光吸收带边显著红移,随着Cu掺杂量的提高,样品光吸收度提高,随着温度的升高,样品紫外-可见光光谱吸收带边红移。

Cu-doped TiO 2 nanoparticles were synthesized through sol-gel method.X-ray diffraction(XRD),transmission electron microscopy(TEM),scanning transmission electron microscope(STEM),X-ray photoelectron spectroscopy(XPS)and UV-Vis absorption spectrum(UV-Vis)were used to characterize the phase composition,average grain size,morphology of TiO2 nanoparticles,chemical valence states and the optical absorption property of TiO2 nanoparticles.The results show that Cu doping suppresses the phase transition of TiO2.CuO appears on the surface of TiO2 particles at 650℃,and the doped Cu ions are in the form of Cu^+.The light absorption bands of Cu-doped TiO2 are red-shifted markedly.The absorbance of the sample increases with the increase of Cu doping amount,and the UV-Vis absorption band is red shifted with the increase of temperature.