分等级结构氧化镍花状微球的制备及其机理研究

Study on Preparation and Formation Mechanism of NiO Hierarchical Nanosheets-flower Microspheres

以六水合硝酸镍为原料,采用简易溶剂热法制备了具有分等级结构的氧化镍纳米片-花状微球。采用X-射线衍射(XRD)、扫描电镜(SEM)和高分辨率透射电镜(HR-TEM)、傅立叶变换红外光谱(FT-IR)等测试技术对其物相形貌进行分析表征。结果表明:在脲素存在条件下,利用醇热法可以合成花状碱式硝酸镍前驱体,在经400℃热处理2 h后,形成了由薄片组成的花状微球,并且由于二次结晶过程,在原来的球体表面形成了扇面状平滑单晶薄片,厚度约为几十纳米。整个晶体生长过程,出现了溶解-再结晶的现象,即可以通过溶解-再结晶的过程来实现对氧化镍微观形貌的调控;并初步探讨了这种具有分等级结构的纳米片-花球结构的形成机理。

NiO nanosheets-flower microspheres with hierarchical structure were synthesized by solvothermal method from urea and Ni（NO3）2·6H2O. The crystal phase was analyzed by X-ray powder diffraction（XRD）,scanning electron microscopy（SEM） and Fourier transform infrared（FT-IR） in this research. The results showed that several smooth and obtuse angle of the fan-shaped multiple wafer nanosheets firmly grow on the surface of flower microspheres under the conditions of urea and heat treatment at 400 ℃ for 2 h,owing to secondary crystallization and high temperature treatment of nickel oxide. Therefore,it is expected to be effective and feasible that the nickel oxide could adjust the morphology of their own existence by dissolving- recrystallization process under the proper conditions. The forming mechanism of flower-like NiO nano-architectures was preliminarily analyzed.