(中山大學(xué)物理系,廣州510275)
摘 要: 采川惰性氣體保護蒸發(fā)凝聚技術(shù),制備了粒徑為4~15nm的稀土金屬Gd微粉。利用小角X射線散射(SAXS)、X射線衍射曲線寬化(XRD)、喇曼散射光譜(RSS)及電子顯微鏡(TED)對所制備的納米Gd微粉(nm-Gd)進行了較廣泛和深入的微觀分析,探討了nm-Gd微粉的粒徑分布及其結(jié)構(gòu)特征。nm-Gd體系的平均粒徑d與制備氣壓P符合如下線性關(guān)系:d = a + blnP。粒徑分布函數(shù)符合Rayleigh統(tǒng)計分布,這不同于一般文獻中采用TEM方法分析得出的對數(shù)正態(tài)分布。此外還對nm-Gd體系的比表而積、表而原子百分比及界面體積分?jǐn)?shù)等結(jié)構(gòu)參數(shù)進行了評估,以揭示它們與平均粒徑d的關(guān)系。實驗結(jié)果與理論計算曲線能較好吻合。
關(guān)鍵字: 稀土元素 納米材料 微觀分析
OF NANOMETER GADOLINIUM POWDERS
(Department of Physics,Zhongshan University,Guangzhou 510275)
Abstract:Nanometer-size gadolinium powders (nm-Gd) have been prepared by means of condensation of evaporating Gd atoms within inert gas atmosphere. The microscope analysis, based on both measurements of small angle X-ray scattering (SAXS), X-ray diffraction (XRD), Raman scattering spectrum (RSS) and observation of transmission electron microscope (TEM), have been carried out in order to evaluate the size and its distribution of as-prepared nm-Gd powders. It turns out that the size distribution of nm-Gd powders meets very well with the distribution function of Rayleigh instead of logarithm. The mean size of nm-Gd powders shows a linear relationship with inert-gas pressure as follows:D=a+blnP. A discussion concerning the influence of particle size of nm-Gd powders on nanometer material parameters such as size distribution, specific surface area and percentage of surface atoms have been given in detail.
Key words: rare earth nanometer materials microscope analysis


