铜掺杂TiO_2光催化剂的制备及光催化亚甲基蓝研究

Synthesis and photocatalytic activity of Cu-doped TiO_2 powder

利用溶胶-凝胶法以钛酸四丁酯、硝酸铜为原料制备了不同质量分数铜掺杂的TiO2光催化剂,采用X射线衍射仪（XRD）、比表面积及孔径测定仪（BET）、热失重分析仪（TG-DTA）、扫描电镜（SEM）、X射线能量散射谱仪（EDS）和透射电镜（TEM）对其进行了表征。结果表明,铜掺杂进入TiO2晶格,掺杂后TiO2在400-600℃之间为锐钛矿型结构,700℃时为金红石型结构,掺杂后比表面积降低。以制备的铜掺杂TiO2光催化剂对亚甲基蓝进行光催化降解实验,结果表明,亚甲基蓝的降解率显著提高,当铜掺杂质量分数为0.3%时,TiO2光催化剂4h可降解亚甲基蓝90%左右。

Cu-doped TiO2 powder with different mass percents were synthesized with tetrabutyl orthotitanate as Ti source and copper nitrate as copper source based on sol-gel method.The sampes were characterized by means of X-ray diffraction（XRD）,X-ray energy dispersive spectroscopy（EDS）,low temperature N2 adsorption-desorption（BET）,thermogravimetry（TG-DTA）,scanning electron microscopy（SEM）and transmission electron microscope（TEM）,respectively.The results showed that Cu^2＋ replaced Ti^4＋ and entered into TiO2 lattice surface area,indicated that the main crystalline phase calcined from 400—600℃was anatase TiO2 and obviously changed to rutile TiO2 at 700℃.Methyl blue dye was used as a target to evaluate the photocatalytic activity of samples.When the doping molar ratio of Cu2＋to tetrabutyl orthotitanate was 0.3%,the samples showed the most efficient for degredating methyl blue and the degredation rate were 80% within240 min.