铈-氟-纳米二氧化钛光催化剂的制备及光催化性能研究

Preparation of nano-TiO_2 doped with Ce,F and its performance for photocatalytic degradation of organic pollutions

以四氯化钛、硝酸铈、氟化铵为原料,采用溶胶-凝胶法制备了铈、氟掺杂的纳米二氧化钛三元光催化剂.通过X射线衍射仪(XRD)、扫描电镜(SEM)、能谱仪(EDS)等对三元光催化剂的结构进行了相应的分析表征,结果表明:与市售纯纳米二氧化钛相比,铈和氟掺杂后的三元光催化剂晶相中产生了次晶相和微量相,颗粒中出现新的多边棱块结构,并且光的响应范围拓展到可见光区.使用紫外可见光谱仪测试了催化剂降解下甲基橙的降解率;测试结果表明,在三元光催化剂的作用下,完全降解甲基橙的时间缩短到30min以内;最后,探讨了三元光催化剂的作用机理,通过动力学计算,三元催化剂降解甲基橙的反应符合假一级反应规律.

Preparation of the photocatalyst ,nano‐doped with Ce and F ,using TiCl4 ,Ce（NO3 ）4 and N H4 F by modified sol‐gel method .Crystal form ,surface morphology ,elements and opti‐cal absorption of the ternary photocatalyst and nano‐TiO2 commercially available were char‐acterized by XRD ,SEM ,EDS and UV‐vis DRS .Under the effect of photocatalysts ,the deg‐radation rate of methyl orange was tested by UV‐vis spectroscopy .The results indicated some phenomenon as follows .Compared with pure TiO2 ,there appears minor phase and trace phase in ternary photocatalyst ;There are structure of multilateral block in the particles of ternary photocatalyst ;ternary photocatalyst responded to wider wavelength of light ;And the degradation efficiency of methyl orange was higher .The experiment showed that the degra‐dation of methyl orange was in accordance to pseudo‐first‐order process .From the above , the mechanism of the photocatalytic degradation was explored .