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以氯化镍、草酸铵和氨水为原料,通过沉淀转化制备纤维状前驱体。采用XRD、SEM、IR和DTA/TGA分析手段研究前驱体粉末的成分与形貌。结果表明:在pH=8.4~8.8时得到的前驱体在形貌和成分等方面均不同于在pH=6.0得到的前驱体,且两种条件下所得前驱体热分解的机理也不同。研究前驱体形貌、热分解气氛、温度及时间对镍粉形貌及分散性的影响,发现前驱体粉末在弱还原性气氛、温度为400~440°C下分解30min时,最终产品基本保持前驱体的形貌。得到的纤维状镍粉分散性良好,但每根纤维表面不再光滑,而是具有大量微孔的粗糙形态。
With nickel chloride, ammonium oxalate and ammonia as raw materials, by precipitation conversion preparation of fibrous precursors. The composition and morphology of the precursor powders were investigated by XRD, SEM, IR and DTA / TGA analysis. The results show that the precursors obtained at pH 8.4 ~ 8.8 are different in morphology and composition from those obtained at pH 6.0, and the thermal decomposition mechanism of the precursors is different under the two conditions. The effect of precursor morphology, pyrolysis atmosphere, temperature and time on the morphology and dispersion of nickel powder was investigated. The results showed that the final product was basically retained when the precursor powder was decomposed in a weak reducing atmosphere at a temperature of 400 ~ 440 ° C for 30min The morphology of the precursor. The resulting fibrous nickel powder has good dispersibility, but the surface of each fiber is no longer smooth, but a rough morphology with a large number of micropores.