High temperature ion conductivity and associated defects in strontium titanate and lithium niobate

Dielectric properties and conductivity were studied in a SrTiO3 crystal in a temperature range 350 – 900K. Study alsu was carried out at Ar atmosphere. Data for SrTiO3 were compared with data for LiNbO3 single crystals. The data indicate a possibility of defects association. The defects association effect at high temperatures and ionic conductivity do not depend on precise particularities of the crystal’s structure and carrier type: SrTiO3 has a perovskite structure, carrier is O2-; LiNbO3 – pseudo-ilmenite, carrier - Li+.

本研究在350~900K的温度范围内，对钛酸锶（SrTiO₃）单晶的介电特性与电导率展开了探究。实验同时在氩气（Ar）气氛环境下开展。随后将钛酸锶的实验数据与铌酸锂（LiNbO₃）单晶的测试数据进行了对比分析。实验结果表明体系存在缺陷缔合的可能性。进一步研究发现，高温下的缺陷缔合效应与离子电导率均不受晶体具体结构及载流子种类的影响：钛酸锶为钙钛矿结构，载流子为氧离子（O²⁻）；铌酸锂则为伪钛铁矿结构，载流子为锂离子（Li⁺）。