工艺条件对液相还原法制备的超细钴粒子形貌的影响

摘要

Ultrafine cobalt particles with different morphology were prepared by reducing cobaltous sulfate(CoSO4·7H2O) with hydrazine hydrate(N2H4·H2O) under the ultrasonic radiation, in which seignette salt(C4H4KNaO6·4H2O) acts as complexing agent and the sodium hydroxide(NaOH) acts as pH value regulator, respectively. The effects of reaction temperature, concentration of sodium hydroxide, complex ratio (C4H4O6]2-/Co2+) and ultrasonic power on the morphologies of cobalt particles were investigated. Results show that with increasing reaction temperature and concentration of sodium hydroxide, the morphologies of cobalt particles were changed from spherical particles packing to radicalized sword-like petals packing,and the size of the sword-like petals decreases with increasing the ultrasonic power. The morphologies of cobalt particles were changed from 3-dimension flaky petals to spherical particles packing, with increasing complex ratio. To some extent, the preparation of shape-controlled ultrafine particles was achieved, featuring simplicity, convenience and low cost.%以酒石酸钾钠(C4H4KNaO6·4H2O)为络合剂，氢氧化钠(NaOH)为pH值调节剂，水合肼(N2H4·H2O)为还原剂，通过在液相中还原硫酸钴(CoSO4·7H2O)的方法制备超细钴粒子，研究了反应温度、氢氧化钠浓度、络合比([C4H4O6]2-/Co2+)和超声功率四种工艺因素对钴粒子形貌及晶体结构的影响。结果表明，随反应温度和氢氧化钠浓度的提高，钴粒子由球状小颗粒堆积形貌向剑型花瓣辐射状形貌转变，且剑型花瓣随超声功率的增高而逐渐减小。而随络合比的提高，钴粒子由三维片状形貌向球状小颗粒堆积形貌转变。该制备方法简便，成本低，并在一定程度上实现了形貌可控超细粉的制备。