铜缓蚀作用的光电化学比较
(1.上海电力学院 电化学研究室，国家电力公司热力设备腐蚀与防护重点实验室，上海 200090；
2. 华东理工大学 防腐蚀中心， 上海 200237)
摘 要: 采用光电化学方法和交流阻抗方法对不同浓度的B TA(苯并三氮唑)和5CBTA(5-羧基苯并三氮唑)在硼砂缓冲溶液(pH 9.2)中对铜电极的缓蚀性能作了比较研究。研究发现两者对铜的缓蚀作用机理不同。一定浓度的BTA能使电极表面Cu2O膜的结构改变，在电位正向扫描过程中铜电极光响应由p型转化为n型，并可依此判断缓蚀剂的缓蚀性能，n型光响应越大，缓蚀剂的缓蚀性能越好；而5CBTA能使电极表面的Cu2O膜增多，在电 位负向扫描过程中阴极光电流密度明显增大，并可据此判断缓蚀剂的缓蚀性能， 阴极光电流密度愈大，缓蚀效果越好。同时这两种缓蚀剂均可用φV 和某一较负电位下的阴极光电流密度Jph的大小来判 断缓蚀剂的缓蚀性能，φV和Jph越负，缓蚀性能越好。交流阻抗方法 的结果和光电化学的结果相一致。
关键字: 苯并三氮唑； 5-羧基苯并三氮唑； 铜电极； 光 电化学； 交流阻抗
inhibiting action of BTA and 5CBTA on copper
（1. Electrochemistry Research Center，Shanghai Institute of Electric Power ，
Shanghai 200090， P.R.China：
2. Corrosion Prevention Center，East China University of Science and Technolo gy，
Shanghai 200237， P.R.China）
Abstract: The photoelectrochemistry behaviour of coppere lectrode in buffer bor ax solutions (pH 9.2) containing BTA and 5CBTA was comparatively studied by using photoelectrochemistry technique. The inhibition mechanisms of BTA and 5CBTA for copper corrosion are different. The photoresponse for copper electrode in soluti on containing a certain amount of BTA exhibits n type during anodic polarization ， the bigger then-ype photoresponse，the better the inhibition of the inhib itor; the photoresponse for copper electrode in solutions containing 5CBTA alwayse xhibitsp-type during anodic polarization，but the photoresponse changes evide nt ly during cathodic polarization，the bigger the maximum cathodic photocurrent，the better the inhibition of the the inhibitor. Inhibitors can be evaluated by φV and Jph at a more negative potential，the more negative the φV and Jph，the better the inhibition. The results from photoelectroche mical technique are in agreement with those from AC impedance technique.
Key words: BTA； 5CBTA； copper electrode； photoelect rochemistry； AC impedance
