试验研究涂覆量对RuTiSnMn/Ti阳极电化学性能的影响

EFFECT OF COATED AMOUNT ON ELECTROCHEMICAL PERFORMANCE OF RuTiSnMn/Ti ANODE

用热分解法制备了RuTiSnMn/Ti阳极,通过循环伏安法和交流阻抗法研究了该阳极在3.5%NaCl溶液、0.5mol/LNaOH溶液和混凝土模拟孔隙液中的电化学行为,利用扫描电镜(SEM)对阳极的微观形貌进行了观察,并在4mA/cm2的电流密度下进行了恒电流试验。结果表明:增加涂覆量,可以提高阳极的催化活性;在NaCl和NaOH溶液中,涂覆量加大后氧化膜电阻降低,氧化膜双电层电容变大,法拉第电荷传递电阻减小;涂液浓度和涂覆量对阳极形貌有显著影响;涂覆量增加加大了涂层活性组元的含量,同时延缓了基体的钝化,使阳极寿命明显延长;涂覆量为9.4g/m2时阳极性能满足标准要求。

RuTiSnMn/Ti anode prepared by thermal decomposition was characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in 3.5% NaCl solution, 0.5 mol/L NaOH solution and simulated pore water. The surface morphology was obseved with SEM. Its electrochemical behaviour was further investigated at a current density of 4mA/cm^2. It was found that, with increase of the coated amount, the electrocatalytic activity of the anode was improved, the double layer capacitance in NaCl solution and NaOH solution increased, the oxide film resistance and the charge transfer resistance of faradaic process occurring at the oxide/solution interface in both NaCl solution and NaOH solution decreased. The volume of the precursor solution and coated amount during the preparation process significantly affected the anode morphology. Increasing coated amount led to higher active component content and delay of the passivation of the metal substrate, resulting in longer service time of the anode. The anode with a coated amount of 9.4g/m^2 can meet the requirement of the standard test.