熔盐快速合成Pb_(1-x)La_xTiO_3粉体(英文)

Rapid Synthesis of Pb_(1-x)La_xTiO_3 Powders in Molten Salt Flux

采用全氧化物为原料,利用熔盐法合成了Pb1-xLaxTiO3(0.0≤x≤0.40),当x=0.45时,烧绿石相La2Ti2O7出现。计算了合成反应活化能,并在700℃下在NaCl-KCl体系中仅用5min就合成了Pb0.9La0.1TiO3。Pb1-xLaxTiO3陶瓷在0.00≤x<0.25时,晶体结构为四方相,在0.25≤x≤0.40时为立方相。采用700℃NaCl-KCl和900℃的Na2SO4-K2SO4两种熔盐体系获得了尺寸分布集中的球形颗粒,这些表明熔盐法晶体生长为扩散控制生长机理。

Perovskite-type compounds Pb1-xLaxTiO3 in the composition range of x from 0 to 0.45 were synthesized using simple oxides from 700 ℃ to 1 000 ℃ by molten salt synthesis （MSS） and a small amount of La2Ti207 pyrochlore phase was detected in the XRD patterns for x=0.45. The activation energy for particle growth in MSS was calculated, and the Pb0.9La0.1TiO3 was synthesized at 700℃ for only 5 min. The perovskite phase for the ma- terial prepared was tetragonal for 0.0≤x ≤0.25 and cubic for 0.25 ≤x ≤0.40. The average particle size was different for samples prepared in NaCl-KCl and Na2SO4-K2SO4 system, but the shape was all spherical for samples obtained from both systems. The same spherical shape could be explained by the diffusion control mechanism for the particle growth into spherical shapes.