CaTiO_3纳米粉体溶胶-凝胶法合成、表征及介电特性  

Sol-gel Method Synthesis,Characterization and Dielectric Properties of CaTiO_3 Nano-powders

作　　者：张启龙[1] 王焕平[1] 杨辉[1] 

机构地区：[1]浙江大学纳米科学与技术中心,杭州310027

出　　处：《无机化学学报》2006年第9期1657-1662,共6页Chinese Journal of Inorganic Chemistry

基　　金：浙江省重点科技计划项目(No.2005C21038)资助。

摘　　要：采用无机盐溶胶-凝胶法制备了CaTiO3纳米粉体,采用TG-DTA、XRD、TEM等技术进行了表征,并探讨了CaTiO3纳米粉体烧结特性及介电效应。结果表明,干凝胶800℃低温煅烧可获得粒径分布较窄、平均粒径为60￣70nm的单相CaTiO3纳米粉。纳米CaTiO3粉具有较大的比表面积,使作为粉体烧结驱动力的表面能剧增,促使CaTiO3在1200℃实现致密烧结,比固相法制备的微米粉烧结降低100￣200℃,且具有较宽的烧结温区。与微米级粉体烧结体介电特性相比,纳米粉具有更高的Qf值。纳米CaTiO3粉制备的陶瓷在1250℃烧结2h,获得优良的介电性能:εr=172,Qf=4239GHz,τf=+7.68×10-4℃-1。CaTiO3 nanoparticles were prepared by inorganic salt sol-gel method and characterized by XRD, TG- DTA and TEM techniques. CaTiO3 nanoparticles with a diameter of 60-70 nm and narrow particle size distribution were obtained by calcining the CaO-TiO2 xerogel at 800 ℃. Due to much lager specific area and higher surface activity of CaTiO3 nano-powder, the CaTiO3 ceramics made from the nano-powder can be sintered at 1200℃ to acquire the dense structure. The sintering temperature was 100-200℃ lower than the sample obtained by solid-reaction method using micron powder. At the same time, the sintering range of CaTiO3 ceramics was also widened. The samples prepared from nano-powder had higher quality factor （Qf） values compared to those prepared from micron powder. At the sintering temperature of 1 250 ℃, the CaTiO3 ceramics made from nano-powder had good dielectric properties： εr=172,Qf=4239GHz（f=2GHz）,τf=＋7.68×10^-4℃^-1.

关 键 词：纳米CaTiO3 溶胶-凝胶 介电性能 

分 类 号：O614.231[理学—无机化学] O614.411[理学—化学]