超声辐照对H_2SO_4溶液中镍电极钝化的影响

EFFECT OF ULTRASOUNIC IRRADIATION ON THE PASSIVATION OF NICKEL ELECTRODE IN H 2SO 4 SOLUTION

通过极化曲线及电化学阻抗法研究了４０ｋＨｚ超声辐照对镍电极在Ｈ２ＳＯ４溶液中钝化行为的影响．结果表明，超声辐照可加速传质过程，从而影响Ｎｉ溶解、钝化及过钝化过程的反应速度，增大致钝电流，减小维钝电位区间，增大维钝电流，改变Ｆｌａｄｅ电位，但并不影响致钝电位．

The effects of 40 kHz ultrasounic irradiation on the formation or removal of passive films on the surface of nickel electrode in H 2SO 4 solution have been investigated by electrochemical impedance measurement and anodic polarization curves. It was noticed that the reduced impedance, the increasing critical current density for passivity,the reduced passivity potential range and the shifted Flade potential were owing to the enhanced mass transport in the presence of ultrasounic.