Synthesis and interaction of lanthanide oxide nanoparticles of with amorphous SiO2.
|Małgorzata Małecka , Leszek Kępiński|
Polish Academy of Sciences, Institute of Low Temperature and Structure Research (INTiBS), Okólna 2, Wrocław 50-422, Poland
Synthesis of inorganic material nanoparticles by water in oil (W/O) microemulsion method enables to produce small particles with narrow size distribution. Using this technique, we obtained well-defined 4-5 nm nanoparticles of precursors of lanthanide oxides (La2O3, CeO2, Pr6O11, Tr4O7). Interactions of lanthanide oxide nanoparticles with SiO2 were studied on example of Pr6O11-SiO2 system by transmission electron microscopy (TEM) and X-ray diffraction (XRD). Two different preparation methods were used. In the first, precursor of praseodymium oxide was supported on amorphous SiO2 by impregnation, followed by calcination in oxygen at 4000C, until Pr6O11-SiO2 system (10 % mol Pr6O11 – 90 % mol SiO2) was formed. As revealed by TEM the sample contained small Pr6O11 nanocrystals (4-5 nm) partly aggregated into clusters (10-100 nm). In the second case nanoparticles of praseodymium oxide precursor were immobilized into silica during synthesis, which prevented their agglomeration. As a result of calcination in oxygen at 4000C small amorphous particles of Pr+3 oxide (4-5 nm) uniformly embedded in SiO2 were obtained. Solid state reactions and formation of Pr silicates in both systems were explored in oxidizing atmosphere at temperatures 8000C, 10000C and 11000C.
Presentation: poster at E-MRS Fall Meeting 2005, Laser Ceramic Symposium, by Małgorzata Małecka
See On-line Journal of E-MRS Fall Meeting 2005
Submitted: 2005-07-11 12:13 Revised: 2009-06-07 00:44