Three-dimensional hierarchical nickel-based hydroxides and oxides microspheres and their electrochemical properties

Nickel hydroxides (Ni(OH)₂) with various morphologies, including flower-like, walnut-like and particle-aggregated microspheres, have been successfully synthesised by a surfactant-assisted microwave hydrothermal method. NiO microspheres have been obtained by calcining corresponding Ni(OH)₂ precursors at 400°C for 2 h. The products were characterised by X-ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy and transform electron microscopy. The electrochemical properties of the NiO microspheres with different morphologies were also investigated.