Deposition of Nickel Hydroxide Structures Using the Scanning Electrochemical Microscope

The scanning electrochemical microscope has been applied to drive the deposition of Ni(OH)₂ structures. Nickel hydroxide has been deposited from aqueous solutions onto platinum surfaces as a result of changing the pH locally on the electrode surface. The increase in pH is driven by an oxidation-reduction process, i.e., N, N-dimethyl-4,4’-bipyridinium, MV²⁺, which is reduced at an ultramicroelectrode, diffuses to the surface where it is regenerated upon the reduction of protons, causing a local increase of pH and the deposition of Ni(OH)₂. The different parameters that control the efficiency of the deposition, such as the pH and the concentration of the buffer, have been examined.