氟化物电沉积铬中十八烷基三甲基氯化铵的阻氢作用

Retardation of hydrogen evolution by octadecyl trimethyl ammonium chloride in chromium electrodeposition in fluoride bath

在硫酸铝、草酸钠、硫酸钠、氟化钠及硼酸的混合介质中,用极化曲线法研究了十八烷基三甲基氯化铵(简称1831)在铬电极表面的阻氢作用。采用正交试验,讨论了1831用量、温度、pH和搅拌速率对析氢电位负移量的影响,确定了最佳实验条件为:183120mg/L,温度35°C,pH1.7,搅拌速率0.56mL/s。在该工艺条件下,金属铬沉积的电流效率提高了13.24%。实验证明,1831是氟化物体系中铬电沉积的有效阻氢剂。

The retardation of hydrogen evolution by octadecyl trimethyl ammonium chloride （also known as 1831 surfactant） on chromium electrode was studied by polarization curve method in a bath composed of A12（SO4）3, Na2C204, Na2SO4, NaF and H3BO3. The effects of the dosage of 1831 surfactant, temperature, pH, and stirring rate on the negative shift of hydrogen evolution potential were discussed by orthogonal test. The optimal conditions were determined as follows： 1831 surfactant 20 mg/L, temperature 35 ℃, pH 1.7, and stirring rate 0.56 mL/s. The current efficiency is increased by 13.24% under the optimal conditions. It is proved that 1831 surfactant is effective in retarding the hydrogen evolution during chromium electroplating in fluoride bath.