采用电化学法一步制备了镍醇盐配合物Ni(OEt) 2 (acac) 2 (acac为乙酰丙酮基 ) ,并以其作为前驱体 ,控制一定水解条件制得胶体 ,分别在 4 5 0℃ ,60 0℃煅烧均得到具有立方晶型的纳米NiO粉体 .通过红外光谱 (FT_IR)、核磁共振 (1HNMR)、拉曼光谱 (Ramanspectrum)、X_射线粉末衍射 (XRD)、透射电子显微镜 (TEM)等手段对前驱体和NiO粉体进行了表征 .结果表明 ,电解合成的最佳温度为 30~ 4 0℃ ,不溶性镍醇盐配合物升温到 4 0~ 5 0℃即可溶解 .电解法制备得到的纳米NiO层呈球形单分散结构 ,粒径在 10~ 15nm左右 .本文同时讨论了电合成纳米NiO的反应机理
Metallic nickel was electrochemically dissolved in absolute ethanol and acetylacetone mixed solutions and in the presence of Bu 4NBr (as an electron-conductive additive). The electrolyte solution containing the precursor was then directly hydrolyzed to obtain nanocrystalline NiO. The precursor was characterized by FTIR?HNMR?Raman spectra and the nano-powder was characterized by XRD and TEM. The results showed that the NiO powder after calcined at 450 ℃ had formed the cubic NaCl structure and the nanocrystalline NiO prepared by this method had narrow size distribution of 10~15 nm. Moreover, the product yield could be improved by controlling temperature below 30~40 ℃. The reaction mechanism was also discussed in this paper.
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