GO/TiO_2复合物的制备、表征及其光催化性能研究

Preparation,Characterization and Photocatalysis Properties of Graphite Oxide/Titanium Diaxdide Compound

以Ti(OC4H9)4为钛源,采用溶胶-凝胶法制备了复合氧化石墨(Graphite oxide,GO)二氧化钛粉体(GO/Ti O2),且利用X射线衍射分析(XRD)、比表面积测定(BET)及透射电镜(TEM)等仪器对其进行了初步表征.以罗丹明B(RhB)的光催化实验为探针反应,研究其光催化活性,发现与单纯Ti O2相比,复合纳米粉末的光催化活性有显著的提高.通过粉体的分子荧光光谱(PL)、紫外可见漫反射分析(UV-vis reflection)及电化学性能的测定,发现石墨的引入有助于减少电子的复合效率.同时,采用辣根过氧化物酶(POD)分光光度法、苯甲酸荧光光度法、超氧化物岐化酶(SOD)和KI分光光度法测定降解过程中的氧化物种,结果表明GO/Ti O2光催化机理涉及到超氧自由基的氧化机理,并未涉及催化剂的空穴氧化.

The composite material of graphite oxide and titanium diaxdide powders（GO/TiO2） is prepared by sol-gel method using Ti（OC4H9）4 as titanium source,and preliminarily characterized by means of XPS,BET and TEM.The degradation of rhodamine B（RhB） is the probe reaction to examine its photocatalytic activity.The results indicate that the photocatalytic activity of GO/TiO2 powders has obviously improved compared with the pure TiO2.Meanwhile the introduction of graphite oxide can efficiently decrease the recombination rate of electron/hole pair based on the PL,Uv-vis reflection analysis and the electrochemical performance.In addition,GO/TiO2 photocatalytic process mainly involves superoxide radical oxidation but hole oxidation by means of horseradish peroxidase（POD） spectrophotometric,benzoic acid fluorescence spectrophotometry and superoxide dismutase（SOD） spectrophotometry.