Anodic Synthesis of beta-Ni(OH)(2) Thin Films on Si(100)

摘要

In this work is described the synthesis of Ni(OH)(2) thin films on top of monocrystalline n-type silicon (100) via anodic electrodeposition assisted by light. As electrolyte was employed an aqueous solution of NiSO(4 center dot)6H(2)O. The Ni(OH)(2) electrodeposition was carried out at two NiSO(4 center dot)6H(2)O concentrations, 0.50 and 0.75 M, and at constant electrolyte temperatures ranging from 10 to 25 degrees C. Potentiostatic current density transients, obtained during Ni(OH)(2) deposition, pointed out that the Ni(OH)(2) nucleation dynamics depend on the tested electrolyte conditions. The Ni(OH)(2) films were investigated by contact profilometry, field emission scanning electron microscopy, Raman spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy. The results showed that the as-deposited films correspond to beta-Ni(OH)(2) unstable phase, which is progressively converted, by environment aging in air atmosphere, to alpha-Ni(OH)(2) after similar to 10 days. The beta-Ni(OH)(2) film is stable and its surface presents a uniform and shiny coloring in the entire film. Its surface has a uniform porous nanostructure, which characteristics depends on the synthesis parameters, salt concentration and electrolyte temperature. (C) 2017 The Electrochemical Society. All rights reserved.