采用循环伏安、线性扫描、计时电流和扫描电镜(SEM)方法研究锆在含四丁基溴化铵异丙醇溶液中的腐蚀行为。循环伏安曲线表明，在 Br−击穿钝化膜诱发点蚀前，锆在异丙醇溶液中不发生活性溶解。扫描电子显微镜证实了点蚀的发生，且电位正移，点蚀加剧，深度增加，腐蚀面积增大。随着溶液温度升高，四丁基溴化铵的浓度增大，锆点蚀电位均下降；而随着扫描速度增大，锆点蚀电位升高。腐蚀电流密度随温度升高而增大，锆阳极溶解表观活化能为21.88 kJ/mol。计时电流曲线表明，四丁基溴化铵浓度增大，点蚀诱导时间缩短，点蚀成核和生长速度均增大。该研究结果有利于获得电化学合成异丙醇锆的最佳工艺条件。%Anodic dissolutionbehaviorof zirconium inBun4NBr-contaningisopropanol solution was investigated using cyclic voltammetry, linear sweep voltammetry and chronoamperometry, complemented with a scanning electron microscope (SEM).The voltammograms did not exhibit active dissolutionuntil the breakdown of passive layer induced by aggressive bromide anions.SEM images confirmed the existence of pits on zirconium surface.The depth and breadth of pits were intensified with increasing potential. The pitting potentialshifted negatively as either temperature orBun4NBr concentration was increased, while it increased with increasing scan rate.The corrosion current density increased with increasing temperature. The apparent activation energyof anodic dissolutionofzirconiumwas 21.88kJ/mol. The chronoamperometry revealed that increasingBun4NBrconcentration shortened the incubation time for passivity breakdown and accelerated the pit nucleation and growth. The experimental results were helpfulto obtain the optimum conditions for electrosynthesis of zirconium isopropoxide.
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