嵌埋于Ag基质中纳米Co团簇结构及其磁性的研究

Study on Structure and Magnetic Properties of Co Cluster Embedded in Ag Matrix

基于溅射－气体－聚集（SGA）形成原子团族的原理，提出了蒸发－气体－聚集（EGA）共沉积制备嵌埋团簇新方法，并在方华膜电镜载网和单晶硅片上成功地制备了嵌埋于Ag基质中纳米Co团簇样品。TEM／ED分析表明，样品中Co团族被Ag原子所包裹，有效地阻止了团簇的表面氧化与自聚集，其结构为fcc－Co和fcc－Ag多晶共存形态。VSM磁性测量表明，样品呈现出超顺磁性，随着测量温度的降低，其饱和磁化强度逐渐升高．

A novel method, evaporation-gas-aggregation (EGA ) co-deposition for CoAg embedded cluster preparation is developed in this paper. TEM analysis shows that Co nanometer clusters are well encapsulated in Ag coatings and a multi-crystal form with both Co and Ag fcc structure exists in as-deposited samples, in which surface oxidation and selfaggregation of Co clusters cou1d be avoided effectively. VSM measurement indicates that samples are superparamagnetic and the saturation magnetization increases with the decrease of testing temperature.