Co/Co9S8/ZnO核壳结构纳米微球的制备与表征  

Preparation and Characterization of Co/Co_9S_8/ZnO Core-shell Nanoshperes

作　　者：赖文忠[1,2] 董校捷[1] 黄婧[1] 冷永华[1] 李星国[1] 

机构地区：[1]北京分子科学国家实验室,稀土材料化学及应用国家重点实验室,北京大学化学与分子工程学院,北京100871 [2]三明学院化学与生物工程系,三明365004

出　　处：《无机材料学报》2010年第3期265-271,共7页Journal of Inorganic Materials

基　　金：国家自然科学基金(20671004,20821091,20971009);科技部863项目(2007AA05Z118,2007AA030114);教育部重大培育项目(707002)

摘　　要：在无水无氧条件下通过热分解还原制备Co纳米微粒,利用Co9S8和ZnO晶格的相匹配性,通过层层自组装对Co表面进行修饰,得到Co/Co9S8/ZnO核壳结构纳米微球.采用XRD、TEM、SQUID、光致发光光谱（PL）等对产物进行了表征.通过调节反应参数制备出核壳结构的Co/Co9S8/ZnO复合纳米微球,平均粒径58.8nm,壳层厚度均匀,常温下显示铁磁性,矫顽力为18.7kA/m.PL表明,产物在380~390nm处的带边跃迁不明显,光致发光最强峰在468nm处,属氧缺陷发射峰,研究了影响产物形貌的主要因素.结果表明,以油酸（OLA）及三正辛基氧化磷（TOPO）为溶剂和表面活性剂,Zn（acac）2温度为70℃、用量为1mmol,控制Co的硫化反应时间为5min,有利于核壳结构产物的形成.初步分析了Co/Co9S8/ZnO核壳结构纳米微球的形成机理.Co/Co9S8/ZnO core-shell nanoshperes were successfully prepared via a thermal decomposition in the water and oxygen-free environmert.The lattice-match between Co9S8 and ZnO played a significant role on the layer-by-layer self-assembly of the core-shell nanospheres.The as-synthesized nanospheres were characterized by XRD,TEM,SQUID and Photoluminescence Spectra.By controlling the reaction parameters,the core-shell nanostructure with uniform size of about 60 nm and shell thickness of 13.6nm was obtained.The effects on the shape control of the product were further investigated,and a proper formation mechanism of the Co/Co9S8/ZnO core-shell nanostructures was presumed.The results show that the favorable procedure to obtain the core-shell nanostructure shape is as follows,the reactants of OLA as solution and TOPO as surfactant,and the optimal temperature and quantity for precursor Zn（acac）2 is 70℃ and 1mmol,respectively.In additon,the sulfidation reaction time for Co is 5 min.The products show ferromagnetism at room temperature with a coercive force of 18.7kA/m.In the photoluminescence measurement,the strongest peak at 460nm which is attributed to oxygen defects can be obtained,while the band edge transitions of ZnO between 380nm and 390nm can hardly be observed.

关 键 词：Co/Co9S8/ZnO 核壳结构 纳米微球 制备 光致发光 磁学性能 

分 类 号：TB383[一般工业技术—材料科学与工程] O614[理学—无机化学]