溶胶-凝胶法制备镍掺杂氧化锌粉体

Sol-gel Synthesis of Ni-doped ZnO

采用溶胶-凝胶法制备出掺Ni（摩尔分数）5%、10%和15%（理论含量）的ZnO粉体。对溶胶进行紫外吸收光谱测试表明,乙酰乙酸乙酯与锌或镍的前躯体在乙醇水溶液中发生了化学修饰作用。利用X射线衍射仪、X射线荧光光谱仪、扫描电子显微镜和多功能物性测量系统研究了试样的微观结构、组成、形貌和磁性能。实验结果表明,ZnO中Ni掺杂的摩尔分数为5%时为单相纤锌矿结构,而Ni掺杂的摩尔分数为10%和15%时出现第二相。掺Ni 5%（摩尔分数）的ZnO粉末试样由5~10μm之间的球形粒子组成,而每个球形粒子又由约100 nm的小粒子聚集而成。在300 K下,掺Ni 5%（摩尔分数）的样品具有顺磁性,而掺Ni 10%（摩尔分数）的样品具有铁磁性。

5%,10% and 15%（norminal composition） Ni-doped ZnO samples were prepared via an sol-gel process.UV absorption spectroscopic analysis discloses that chemical modification is achieved by intereaction between Zn or Ni precursor and ethyl acetoacetate.The crystal structure,composition,morphology and magnetic properties were characterized by using X-ray diffraction（XRD）,X-ray fluorescence spectrometry（XRF）,scanning electron microscope（SEM） and physical property measurement system（PPMS）,respectively.XRD results indicate that 10% and 15%（molar fraction） Ni-doped ZnO samples have a wurtzite phase as well as NiO impurity phase while the 5%（molar fraction） Ni-doped sample has a single wurtzite phase.The as-fabricated powder products consist of micrometer-sized sphere particles and each of the sphere particle is composed of small nano particles（about 100 nm）.The 5%（molar fraction） Ni-doped ZnO sample shows paramagnetic effects at room temperature.Room-temperature ferromagnetism is observed in the 10%（molar fraction） Ni-doped ZnO sample.