非水体系中电解镍中间产物制备纳米NiO

采用纯镍为阳极，乙酰丙酮和乙醇的混合溶液中加入少量有机胺导电盐为电解液，施加一定电流使镍溶解，然后将电解液直接水解，控制一定的水解条件，制备得到纳米NiO粉体. 采用拉曼光谱、红外光谱、元素分析、XRD 和TEM 分别对电解得到的纳米NiO前驱体和纳米NiO进行了分析与表征, 并探讨了电化学溶解镍金属法制备纳米NiO反应的影响因素.电化学溶解镍金属得到的前驱体为Ni(OEt)2(acac)2,这种不溶性镍醇盐配合物升温至40～50℃即可溶解于乙醇溶液中,可直接应用于溶胶 凝胶(Sol gel)过程.水解后的纳米NiO呈无定形结构, 350 ℃煅烧后形成立方晶型NaCl结构, 纳米NiO经600 ℃煅烧后粒径分布在5～10 nm. 该方法理论上为二价不溶性金属醇盐经溶胶 凝胶工艺制备纳米氧化物材料提供了一条新的途径.

Preparation of Nanocrystalline NiO by Electrochemical Dissolution of Nickel in Nonaqueous Solution

Metallic nickel was electrochemically dissolved in absolute ethanol and acetylacetone solution in the presence of Bu4NBr(as electron conductive additive). The electrolyte solution containing the precursor was then directly hydrolyzed to obtain nanocrystalline NiO. The precursor was characterized by FTIR、1HNMR、Raman spectra and the nano powder was characterized by XRD and TEM. The results showed that the NiO powder after hydrolysis was amorphous but formed the cubic NaCl structure when calcined at 350 ℃,the NiO powder have a narrow size distribution of 5～10 nm after annealed at 600 ℃. Characterization of the electrochemical product revealed that Ni(OEt)2(acac)2 was formed by anode dissolution of nickel in ethanol and acetylacetone mixed solution. The experiments also showed that the precursor of the nanocrystalline NiO prepared by this method can be dissolved in ethanol solution when temperature increase to 40～50 ℃ region.