镀镍溶液中硼酸作用机理的研究

FUNCTIONS OF BORIC ACID IN NICKEL PLATING SOLUTION

利用酸碱滴定、电毛细方法及动电位扫描法研究了硼酸在镀镍溶液中的作用机理.酸碱滴定的结果表明,当溶液 pH≈9时硼酸具有最大的缓冲容量.在酸性镀镍溶液中,由于阴极伴有氢的析出,pH 值升高,硼酸能起缓冲作用.电毛细测定和动电位扫描实验表明,硼酸具有一定的表面活性,在一定的电位范围内,它吸附在电极表面,并影响氢的析出过程.

Functions of boric acid in nickel electroplating solution are studied by titration method,electrocapillary measurement and scanning voltammetry. The result of titration shows the maximum buffer capacity of boric acid is at pH 9.Boric acid acts as a buffer in the cathodic region of nickel plating solution,when pH is raised by hydrogen evolution.The results of electrocap- illary measurement and scanning voltammetry show that boric acid is a kind of surface-active substances.It is adsorbed at the surface of the electrode, which influenced the evolution of hydrogen.