摘要
空气中烧结各种施主掺杂的BaTiO3陶瓷时,存在一种电阻率反常现象。从热力学以及晶体结构化学的角度出发,对临界施主掺杂浓度进行了理论计算和推导。结果表明:释放氧所需的能量与施主离子的种类无关,因而临界施主掺杂浓度为一定值;临界掺杂浓度时的晶粒尺寸越小,在晶粒重结晶过程中临界施主掺杂浓度就越大。
A longstanding problem in the insulating and/or semiconducting behavior of donor-doped BaTiO3 ceramics is the occurrence of a room-temperature resistivity minimum in compositions doped with different donor cations. From the viewpoint of thermodynamic and structural chemistry, the critical dopant concentration was calculated by a theoretical model. The results show that the energy of the expulsion of oxygen is does not depend on the kinds of donor cations; as a result, the critical concentration is a constant. The smaller the grain size is at the critical concentration, the higher the critical concentration is during the recrystallization of BaTiO3.
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2007年第7期812-816,共5页
Journal of The Chinese Ceramic Society
基金
国家自然科学基金(50607013)
人事部留学人员科技活动择优(2007)资助项目
关键词
施主掺杂
钛酸钡
陶瓷
临界掺杂浓度
donor-doped
barium titanate
ceramics
critical dopant concentration
