Synthesis, spectroscopic analysis and electrochemical performance of modified β -nickel hydroxide electrode with CuO

Abstract

Abstract In the present work, a modified β -nickel hydroxide ( β -Ni(OH) 2 ) electrode material with CuO has been prepared using a co-precipitation method. The structure and property of the modified β -Ni(OH) 2 with CuO were characterized by X-ray diffraction (XRD), Fourier Transform infra-red (FT-IR), Raman and thermal gravimetric-differential thermal analysis (TG-DTA) techniques. The results of the FT-IR spectroscopy and TG-DTA indicate that the modified β -Ni(OH) 2 electrode materials contain intercalated water molecules and anions. A pasted–type electrode was prepared using nickel hydroxide powder as the main active material on a nickel sheet as a current collector. Cyclic voltammetry (CV) and Electrochemical impedance spectroscopy (EIS) studies were undertaken to assess the electrochemical behavior of pure β -Ni(OH) 2 and modified β -Ni(OH) 2 electrode with CuO in a 6 M KOH electrolyte. The addition of CuO into β -nickel hydroxide was found to enhance the reversibility of the electrode reaction and also increase the separation of the oxidation current peak of the active material from the oxygen evolution current. The modified nickel hydroxide with CuO was also found to exhibit a higher proton diffusion coefficient and a lower charge transfer resistance. These findings suggest that the modified β -Ni(OH) 2 with CuO possesses an enhanced electrochemical response and thus can be recognized as a promising candidate for battery electrode applications.