氢氧化镍纳米晶的水热合成和结构表征

用水热法在180℃合成了非球形的Ni(OH)2纳米晶，并用X射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)、透射电镜(TEM)和高分辨透射电镜(HRTEM)等技术对其形貌和结构作了表征. 结果表明，Ni(OH)2纳米晶的生长习性和形貌都强烈依赖于前驱物溶液的pH值. 在较高的pH值(13.40)下，产物主要是六角片状粒子，而在近中性条件(7.80)下，产物主要是不规则形貌的粒子. 在pH值较高的条件下，除了通常的Ostwald ripening 晶体生长粗化机理外，合并生长机理对纳米晶生长过程也发挥了作用.

Hydrothermal Growth and Structural Characterization of Ni(OH)2 Nanocrystals

The hydrothermal growth of non-spherical Ni(OH)2 nanocrystals was achieved at 180℃. Basic solutions of nickel nitrate with different pH values were used as the precursor solutions. X-ray diffraction, FT-IR spectroscopy, transmission electron microscope (TEM) and high-resolution transmission electron microscope (HRTEM) were employed to analyze the crystalline structure and particle morphology of the synthesized Ni(OH)2 nanocrystals. The results reveal that the growth habits and morphologies of the as-prepared nanocrystals are strongly dependent on the pH value of the precursor solution. At a relatively high pH value of 13.40, the products are mainly hexagonal platelets, while they are irregularly shaped particles at the pH value of 7.8. The impact for the pH value on the difference in crystal growth habits is discussed. In addition, both Ostwald ripening and oriented aggregation mechanisms are supposed to be responsible for the growth process of the nanocrystals at the relatively high pH value.