摘要
采用通常的溶液沉淀、微乳液及均匀沉淀等溶液方法制备纳米氧化镱 .TEM观测显示 ,采用H2 O2 的溶液沉淀法和采用CTAB的均匀沉淀法 ,都可得到有较好分散、尺度约为 10nm的球形粒子 ;XRD分析表明 ,经 65 0℃焙烧后的氧化镱均为立方结构 ,采用H2 O2 的溶液沉淀法所得氧化镱的晶粒尺寸为 9 4nm ,采用CTAB的均匀沉淀法所得氧化镱的晶粒尺寸为6 9nm ;基于低温N2 吸附表征结果发现 ,微乳液法制得的Yb2 O3 的比表面积较低 ,采用H2 O2 的溶液沉淀法可以制得比表面积为 47 7m2 /g、等效粒径为 13 6nm的Yb2 O3 ,采用CTAB的均匀沉淀法所得氧化镱比表面积为 63 2m2 /g ,等效粒径为 10 3nm .表面活性剂与水合氧化镱沉淀物间的相互作用 ,可能对所得氧化镱的热稳定性有重要影响 .
Several wet chemical methods, such as conventional precipitation, microemulsion route and homogeneous precipitation, have been used to prepare nanosized ytterbium oxides. After being calcined at 650 degreesC, well-dispersed spherical particles with size of about 10 nm characterized by TEM observations can be prepared by hydrogen peroxide- or CTAB-aided precipitation process. XRD results show that the as-prepared samples are cubic ytterbium oxides with the crystal sizes of 9.4 nm for hydrogen peroxide-aided way and 6.9 nm for CTAB-containing route. Nitrogen adsorption characterization at 77 K indicates that (i) the present microemulsion process gives a sample with the lowest specific surface area compared with other methods, (ii) ytterbium oxides with specific surface areas of 47.7 m(2)/g (equivalent diameter of 13.6 nm) and 63.2 m(2)/g (equivalent diameter of 10.3 nm) can be prepared by hydrogen peroxide-aided way and CTAB-containing homogeneous precipitation process, respectively. The interaction between the surfactants and the hydrous ytterbia may play an important role in the thermal stability of the derived Yb2O3.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2004年第18期1845-1848,共4页
Acta Chimica Sinica
基金
国家重点基础研究发展规划 (No.G1 9990 2 2 4 0 8)
国家自然科学基金 (Nos.2 0 0 2 30 0 1
2 0 0 2 1 0 0 2 )资助项目
关键词
纳米氧化镱
湿化学法
制备
溶液沉淀
均匀沉淀
比表面积
ytterbia
ytterbium oxide
nanocrystal
high specific surface area
wet chemical method
conventional precipitation
homogeneous precipitation
