Formation mechanism of nickel hydroxide in system Ni(NO3)2—NaOH

основного ABSTRACT Nickel hydroxide is used an active substance for accumulators and supercapacitors, which are widely used as power sources for various electric devices and electronics. According to literature the formation of divalent metal hydroxides such as zinc and cadmium hydroxides(Zn(OH) 2 , Cd(OH) 2 ) occurs in two stage: 1) precipitation of metal hydroxyl salt; 2) reaction of hydroxyl salt with hydroxyl groups with formation of metal hydroxide. Though the nickel hydroxyl nitrate is known, the information regarding its formation mechanism and composition is limited. Aim of the work was to establish the formation mechanism of nickel hydroxide from nitrate precursor and to establish the composition of formed precipitate. In order to achieve the set aim, the analysis of Ni(NO 3 ) 2 — NaOH system has been carried out using combined method of conductometric and potentiometric titration. It had been established that process of nickel hydroxide formation from nitrate solution occurs in two stages: 1) precipitation of basic nickel nitrate; 2) transformation of basic nickel nitrate into hydroxide. It had been established that composition of primary precipitate correspond to the formula Ni(NO 3 ) 0.13 (OH) 1.87 .