Liu Chuyang, Zhang Yujing, Jia Jingguo, Sui Qiang, Ma Ning, Du Piyi
State Key Laboratory of Silicon Materials, Department of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, P.R. China.
Sci Rep. 2015 Apr 2;5:9498. doi: 10.1038/srep09498.
Multiferroic ceramics with extraordinary susceptibilities coexisting are vitally important for the multi-functionality and integration of electronic devices. However, multiferroic composites, as the most potential candidates, will introduce inevitable interface deficiencies and thus dielectric loss from dissimilar phases. In this study, single-phased ferrite ceramics with considerable magnetic and dielectric performances appearing simultaneously were fabricated by doping target ions in higher valence than that of Fe(3+), such as Ti(4+), Nb(5+) and Zr(4+), into BaFe12O19. In terms of charge balance, Fe(3+)/Fe(2+) pair dipoles are produced through the substitution of Fe(3+) by high-valenced ions. The electron hopping between Fe(3+) and Fe(2+) ions results in colossal permittivity. Whilst the single-phased ceramics doped by target ions exhibit low dielectric loss naturally due to the diminishment of interfacial polarization and still maintain typical magnetic properties. This study provides a convenient method to attain practicable materials with both outstanding magnetic and dielectric properties, which may be of interest to integration and multi-functionality of electronic devices.
具有共存的非凡磁化率的多铁性陶瓷对于电子设备的多功能性和集成至关重要。然而,作为最具潜力的候选材料,多铁性复合材料会不可避免地引入界面缺陷,从而导致不同相之间的介电损耗。在本研究中,通过将比Fe(3+)价态更高的目标离子(如Ti(4+)、Nb(5+)和Zr(4+))掺杂到BaFe12O19中,制备出了同时具有可观磁性能和介电性能的单相铁氧体陶瓷。从电荷平衡的角度来看,通过高价离子取代Fe(3+)产生了Fe(3+)/Fe(2+)对偶极子。Fe(3+)和Fe(2+)离子之间的电子跳跃导致了巨大的介电常数。同时,由于界面极化的减弱,由目标离子掺杂的单相陶瓷自然地表现出低介电损耗,并且仍然保持典型的磁性能。本研究提供了一种方便的方法来获得兼具优异磁性能和介电性能的实用材料,这可能会引起电子设备集成和多功能性方面的关注。