掺杂的阳离子缺陷型磷灰石La9.33-2x/3MxSi6O26(M=Mg,Sr,Ca)的合成及离子导电特性

• Published in: 中国化学工程学报（英文版） Vol. 16; no. 3; pp. 488 - 491
• Main Authors: 袁文辉, 顾亚萍, 李莉
• Format: Journal Article
• Language: Chinese
• Published: Guangdong Key Laboratory of Green Chemicals, College of Chemical Engineering and Energy, South China University of Technology, Guangzhou 510640, China%College of Environmental and Engineering, South China University of Technology, Guangzhou 510640, China 2008
• Subjects: cation vacancies; apatite; ionic conductivity; dopant; sol-gel
• ISSN: 1004-9541

TQ02; Apatite-type lanthanum silicate with special conduction mechanism via interstitial oxygen has attracted considerable interest in recent years. In this work, pure powder of La9.33-2x/3 MxSi6O26 (M=Mg, Ca, Sr) is prepared by the sol-gel method with sintering at 1000℃. The powder is characterized by X-ray diffraction (XRD) and scanning electron micrograph (SEM). The apatite can be obtained at relatively low temperature as compared to the conventional solid-state reaction method. The measurements of conductivity of a series of doped samples La9.33-2x/3 MxSi6O26 (M=Ca, Mg, Sr) indicate that the type of dopant and the amount have a significant effect on the conductivity. The greatest decrease in conductivity is observed for Mg doping, following the Ca and the Sr doped apatites. The effect is ultimately attributed to the amount of oxygen interstitials, which is affected by the crystal lattice distortion arising from cation vacancies.