自组装花状结构Ni(OH)_2的微波水热合成与表征

Microwave hydrothermal synthesis and characterization of self-assembled flower-like nickel hydroxide

以六水合硝酸镍为镍源,尿素为水解控制剂及聚乙二醇(PEG)为表面活性剂,采用微波水热法成功合成了由亚微米片自组装而成的花状结构Ni(OH)2,并通过进一步的热处理得到相同结构形貌的NiO。利用XRD、SEM、TEM、FTIR、UV-Vis等方法对产物进行了表征,结果表明,自组装花状结构Ni(OH)2的直径为2.5～4.0μm,单个亚微米片的厚度约10～20nm,宽约在0.5～1.5μm之间。紫外吸收光谱分析表明,NiO样品的禁带宽度(Eg)值为3.27eV,有明显红移现象。将所制备的氢氧化镍制成电极,其电化学性能测试表明它具有良好的可逆性。

The Ni（OH）2 architectures with flower-like morphology assembled from nanosheets have been successfully synthesized through a microwave-assisted hydrothermal method using urea as a hydrolysis-controlling agent and polyethylene glycol（PEG） as a surfactant.The NiO architectures with similar morphology were obtained by a simple thermal decomposition process of the precursor Ni（OH）2.The as-obtained products were well characterized by XRD,TG-DTA,SEM,TEM,FTIR and UV-Vis.The experimental results shown that flower-like Ni（OH）2 architectures with a diameter of 2.5-4.0μm are assembled from nanosheets with a thickness of 10-20nm and width of 0.5-1.5μm.The UV-Vis experimental results shown that the band gap of the as-synthesized NiO samples was about 3.27eV,which shows obvious red-shift compared with that of the bulk NiO.The electrochemical performance of the Ni（OH）2 was investigated by means of the experiment of cyclic voltammetry.The results indicated that it was reversible.