Partially reduced β-Ni(OH)2 nanoplates with enhanced performance

초록

Nickel-based materials have been widely utilized for energy storage and conversion system such as fuel cell, metal-air battery, and supercapacitor. In addition, these catalysts have also attracted attention as a promising electrode material for electrochemical water splitting. In this work, β-Ni(OH)2 nanoplates 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 fabricated nickel hydroxide was analyzed by X-ray diffraction (XRD). The surface compositions of prepared β-Ni(OH)2 catalysts were assessed by X-ray photoelectron spectroscopy (XPS). The surface area and pore size distribution was determined by Brunauer-Emmett-Teller (BET). The electrochemical properties were investigated by linear sweep voltammetry (LSV), cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) in a standard three electrode system using a potentiostat. The partially reduced β-Ni(OH)2 nanoplates exhibited higher electrochemical activity and stability than pristine sample, which were attributed to abundant oxygen vacancies.