| A new method, namely, coordination homogenious precipitation method was described to synthesize nanometer nickel hydroxide and nickel oxide powders with different shapes. Transmission electron microscope(TEM), powder X–ray diffraction(XRD), thermal analysis(TG-DTA), infrared absorption spectroscopy(IR), differential scanning calorimetry(DSC) were used to characterize the microstructure and morphologiy of the products, the application of nanometer Ni(OH)2 in the MH/Ni battery was also investigated preliminarily.Nanometer Ni(OH)2 was synthesized by using the ammonia and nickel nitrate as the raw materials, the technological process conditions were explored and optimized in great depth, and the optimum conditions for preparing Ni(OH)2 nanoaprticles were obtained. The sizes and shapes of the particles were controlled by the reaction conditions and the additive of surfactant, and the nanometer Ni(OH)2 particles of spherical shape, needle-like shape and thin flake-like shape were formed, the XRD result shows that nanometer Ni(OH)2 prepared in this study are all beta-type crystal. Using the as-synthesized nanometer Ni(OH)2 as precursor, the nano NiO particles of needle, pole or granule in shape were formed by controlling the heat-treating temperature and time of the precursor.The nanometer basic nickel carbonate precursor were prepared firstly, ammonia water, ammonium bicarbonate and nickel nitrate as the raw materials, then the nanometer NiO particles obtained by drying and calcination of the precursor. The prepared NiO particles were well dispersed under the optimum conditions, and the mean size was about 512nm.Compared with the existing method for preparing nano Ni(OH)2 and NiO, this method has many advantages: mild reaction conditions, simple production process, short process flow and low cost. The nanometer particles with narrow size distribution and good dispersivity can be synthesized by this method, and thus it has a great application prospect.In addition, the electrodes were prepared using the as-synthesized nanometer Ni(OH)2, and its electrochemical performances were investigated preliminarily. The results show that the performance of the electrode prepared by pure nanometer Ni(OH)2 is not good, but the discharge performance is improved obviously when 10% of nanometer Ni(OH)2 are added into the conventional spherical Ni(OH)2, so the obtainedβ-Ni(OH)2 nanocrystals are expected to be a promising additive material for...
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