Mn-Mo-Ce氧化物阳极在海水中电催化及稳定性能研究

Electrocatalytic Activity and Durability of Mn-Mo-Ce Oxide Anode in Sea Water

采用阳极电沉积方法在Mn-Mo氧化物阳极基础上,通过向镀液中加入稀土Ce Cl3制备了Mn-Mo-Ce氧化物阳极材料,采用循环伏安、Tafel极化曲线和电化学阻抗谱等电化学方法测试了Mn-Mo-Ce氧化物阳极的电催化性能;采用加速寿命实验及对氧化物阳极表面形貌观察,研究了Mn-Mo-Ce氧化物阳极材料在海水介质中的稳定性能。结果表明:稀土Ce的掺杂在一定程度上细化了Mn-Mo-Ce氧化物的微观结构,镀层结合致密,表面均匀分布有细小胞状物,微裂纹细密且数量较多,使电极表面的活性点数量增多,增大了真实表面积,提高了Mn-Mo-Ce氧化物电极的电催化性能;Mn-Mo-Ce氧化物阳极电解过程以氧化物溶解及剥落为主要破坏形式,Mn-Mo-Ce氧化物电极在海水介质中具有较好的稳定性,加速电解寿命可达1595 h,比Mn-Mo氧化物阳极高约207 h。

Mn-Mo-Ce oxide anode material was prepared on Mn-Mo oxide anode by electrodeposi- tion in an electrolyte with addition of CeCI3. The electrocatalytic properties of Mn-Mo-Ce oxide anode were assessed by methods of cyclic voltammetry, Tafel polarization curves and electrochemical imped- ance spectroscopy. The durability of the Mn-Mo-Ce oxide anode in sea water was examined by accelerat- ed test and the surface morphology of the oxide anode was characterized by SEM. Results show that with the doping of Ce-oxide, the formed Mn-Mo-Ce oxide coating is dense with a fine microstructure, of which on the surface there exists uniformly distributed fine vesiculates and a large number of micro- cracks, therewith resulting in the increase of the real surface area and the number of active points on the surface and in turn enhance the electrocatalytic performance of Mn-Mo-Ce oxide electrode. The main de- struction form of the Mn-Mo-Ce oxide in the anode electrolysis process is dissolution and spallation of ox- ides. Mn-Mo-Ce oxide electrode has good durability in sea water, with a life time up to 1595 h,i.e. about 207 h higher than that of Mn-Mo oxide anode.