Abstract (Li + Nb) co-doped (Li + Nb)xFe2-xO3 (with x = 0.0005, 0.005, 0.05, and 0.1) ceramics were prepared by sol-gel method. Their structural, dielectric, humidity, and magnetic properties were investigated. Colossal permittivity (~104) was approached or achieved in all doped samples even with a very small doping level of x = 0.0005. The colossal permittivity behavior is composed of two dielectric relaxations with the low-temperature one being a polaron relaxation due to electrons hopping between Fe3+ and Fe4+ ions and the high-temperature one being a Maxwell-Wagner relaxation caused by humidity-sensing properties.

中文翻译：

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(Li+Nb) 共掺杂 Fe2O3 陶瓷中的巨大介电常数

摘要 采用溶胶-凝胶法制备了(Li+Nb)共掺杂(Li+Nb)xFe2-xO3(x=0.0005、0.005、0.05和0.1)陶瓷。研究了它们的结构、介电性、湿度和磁性。即使在非常小的掺杂水平 x = 0.0005 的情况下，所有掺杂样品都接近或达到了巨大的介电常数 (~104)。巨大的介电常数行为由两种介电弛豫组成，低温一种是由于 Fe3+ 和 Fe4+ 离子之间的电子跳跃引起的极化子弛豫，而高温一种是由湿度传感特性引起的 Maxwell-Wagner 弛豫。