模拟水中白铜B30耐蚀性影响因素的光电化学研究
Photoelectrochemical Study of Influence Factors on Corrosion Resistance of Cupronickel B30 in Simulated Water
Abstract
用动电位伏安法和光电化学方法对模拟水中白铜B30耐蚀性影响因素进行了研究.白铜B30表面膜显示p-型光响应,光响应来自电极表面的Cu2O层,在模拟水溶液中表面膜的半导体性质会发生转变,由p-型转为n-型;在不同Cl-,SO24?浓度的模拟水溶液中,电位正向扫描时呈现阳极光电流,电位负向扫描时随着Cl-,SO24?离子浓度的增加,光响应由p-型向n-型转变,阳极光电流峰面积与阴极光电流峰面积之比增大,耐蚀性能降低;随着温度的升高,白铜B30的耐蚀性能降低;在pH=7～9之间,其耐蚀性能随着pH的升高而提高,当pH>9时,其耐蚀性能随着pH的升高呈降低趋势. Influence factors on semiconduction properties of oxide films on a cupronickel electrode in the simulated water was studied by cyclic voltammetry and photocurrent response method. The cupronickel electrode showed p-type photoresponse, which came from Cu2O layer on its surface. The photoresponse changed to n-type in the simulated water. The transition from p-type to n-type might be related to the doping of Cl- and SO 42? anions into Cu2O film. It did not show n-type photoresponse when the cupronickel elec- trode was immersed in the simulated water containing some sulfide. It was shown that the degree of corro- sion increased with the concentration of these anions and temperature. In addition, as the pH increased be- tween 7 and 9, the corrosion resistance of B30 was enhanced, while it lowered as the pH was beyond 9.