The Effect of Current and Nickel Nitrate Concentration on the Deposition of Nickel Hydroxide Films

Abstract

An electrochemical quartz crystal nanobalance (EQCN) has been utilized to measure the mass of films electrochemically deposited from solutions. The objective of this work was to quantify electrochemical deposition as a function of deposition conditions. The changing mass recorded on the EQCN was demonstrated to be the result of deposition. Deposited mass was observed to increase proportionally with applied charge as suggested by previous investigators. Most significantly, the rate of deposition was found to decrease more than an order of magnitude as the concentration increased from 0.2 to 2.0M. The effect of concentration is shown to be related to Ni(II) concentration as opposed to solution pH or concentration. An empirical correlation is given to predict deposition rates in solutions ranging from and at current densities ranging from . The decreased deposition rates in concentrated are attributed to the formation of intermediate species [e.g., or ] which diffuse away from the reaction interface before deposition can occur.