Fe~(3+)、Ce~(3+)掺杂SnO_2/C/Ti催化电极上苯酚的电化学行为研究

采用溶胶-凝胶法合成Fe3+、Ce3+掺杂SnO2/C胶体,通过Vulcan XC-72炭黑负载制备炭载锡系氧化物电催化剂。经X射线粉末衍射(XRD)考察了催化电极的元素组成,利用循环伏安法(CV)研究苯酚在电极上的氧化降解,考察了不同的掺杂元素、不同的掺杂量、制备工艺等因素对电极催化性能的影响。结果表明:所合成的电催化剂中的金属氧化物的主要相态为金红石型SnO2;Sn系列氧化物电极对苯酚具有一定的催化能力,适量Sb、Ce、V、Yb元素的掺杂有利于电极电化学性能的提高,Sb(2.5%)和Ce(2.5%)双掺的SnO2/C/Ti电极的氧化峰电流最大,苯酚在电极表面氧化时,均会产生一层疏松的钝化膜,苯酚仍可以穿透这层钝化膜继续在电极上氧化。

Study on the Electrochemical Behaviors of Phenol on FeFe3+and Ce3+Doped SnO2/C/Ti Anodes

Fe~(3+) and Ce~(3+) doped SnO_2/C were prepared by sol-gel method and Vulcan XC-72 carbon was used as carrier due to its porous structure. The composition of catalytic electrode was studied with XRD. The electroxidative behaviors of different doping elements were studied by electrochemical methods such as cyclte voltammetry (CV). The results indicated that the prepared samples were rutile SnO_2. These electrodes had electrocatalytic ability for phenol oxidation. Doping elements (Sb、Ce、V、Yb) and higher temp rature are beneficial for the improvement of DSA electrocatalytic ability. Sb(2. 5%) and Ce(2. 5%) co-deeping electrode had the highest peak current according to a3 which was the first step in phenoxy dectrcoxidation attributed to the formation of a phenoxy radical. Complete electrode passivation was not observed on polyoxyphenylene film which had covered dorninantly the coating surface.