摘要
以溶胶-凝胶法和固相反应方法分别合成了硅酸盐氧基磷灰石A2La8(SiO4)6O2(A=Ca,Sr,Ba),经XRD表征,证明所得产品为磷灰石相。和固相反应方法相比,溶胶-凝胶法合成磷灰石反应温度低,高温焙烧时间短。电化学阻抗谱研究表明:随着A(A=Ca,Sr,Ba)半径的增大,电导率也逐步加大,活化能却逐步减小。700℃时溶胶-凝胶法合成的Ba2La8(SiO4)6O2的电导率(4.42×10-6 S·cm-1)要比固相反应法合成的电导率大一个数量级。离子迁移数和氧分压对电导率的研究表明,主要的电荷载体是O2-离子。
The synthesis of the silicate oxyapatites A2La8(SiO4)6O2 (A=Ca,Sr,Ba) via a sol-gel method and solid-state reactions were studied contrastively. The reaction time and temperature were decreased greatly by sol-gel method than solid-state reactions .The apatite phases were characterized by X-ray diffraction (XRD), electrical conducting properties were studied by electrochemical impedance spectroscopy (EIS). It was found that the ionic conduction in A2La8(SiO4)6O2 (A=Ca,Sr,Ba) increases with increasing radius of A2+ cations, whilst the activation energy decreases. The conductivity of Ba2La8(SiO4)6O2 by sol-gel method is 4.42×10-6S·cm-1,it is higher about one orders of magnitude than by solid-state reactions at 700℃. Transport number of oxygen ion and the dependence of electrical conductivity on oxygen partial pressure indicate that the charge carriers of the silicate oxyapatite are oxygen ions.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2008年第2期220-224,共5页
Bulletin of the Chinese Ceramic Society
基金
黑龙江省自然科学基金重点项目(ZJG03-4)
黑龙江省科技攻关项目(GC04A207)资助
关键词
溶胶凝胶法
固相反应方法
硅酸盐氧基磷灰石
电化学阻抗谱
sol-gel method
solid-state reactions
silicate oxyapatite
electrochemical impedance spectroscopy (EIS)