β-Nickel hydroxide as an enhanced electro-catalyst for water oxidation in alkaline solution

초록

Nickel-based materials are widely utilized for energy storage system such as fuel cell, metal-air battery, and supercapacitor. These catalysts have also attracted attention as a promising electrode material for electrochemical water splitting. In this work, β-nickel hydroxides with oxygen vacancies were successfully synthesized via a hydrothermal method and heat treatment with hydrogen and argon atmosphere. The surface properties of the samples were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The crystallinity of the synthesized nickel hydroxide were analyzed by X-ray diffraction (XRD). The surface compositions of prepared nickel hydroxide were assessed by X-ray photoelectron spectroscopy (XPS). The surface area and pore size distribution was determined by Brunauer-Emmett-Teller (BET) and Barrett-Joyner-Halenda (BJH), respectively. The electrochemical properties were investigated by linear sweep voltammetry (LSV) and cyclic voltammetry (CV) in a standard three electrode system using a potentiostat. The partially reduced nickel hydroxide exhibited higher electrochemical activity and stability than pristine sample.