Liu Xiaolin, Wang Bin, Huang Xiaofeng, Dong Xinwei, Ren Yanping, Zhao Haixia, Long Lasheng, Zheng Lansun
Collaborative Innovation Center of Chemistry for Energy Materials, State Key Laboratory of Physical Chemistry of Solid Surfaces, and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, People's Republic of China.
Department of Physics and Institute of Theoretical Physics and Astrophysics, Xiamen University, Xiamen 361005, People's Republic of China.
J Am Chem Soc. 2021 Apr 21;143(15):5779-5785. doi: 10.1021/jacs.1c00601. Epub 2021 Apr 13.
Great importance has been attached to magnetoelectric coupling in multiferroic thin films owing to their extremely practical use in a new generation of devices. Here, a film of [(-CH)N][FeFe(dto)] (; dto = COS) was fabricated using a simple stamping process. As was revealed by our experimental results, in-plane ferroelectricity over a wide temperature range from 50 to 300 K was induced by electron hopping between Fe and Fe sites. This mechanism was further confirmed by the ferroelectric observation of the compound [(-CH)N][FeZn(dto)] (; dto = COS), in which Fe ions were replaced by nonmagnetic metal Zn ions, resulting in no obvious ferroelectric polarization. However, both ferroelectricity and magnetism are related to the magnetic Fe ions, implying a strong magnetoelectric coupling in . Through piezoresponse force microscopy (PFM), the observation of magnetoelectric coupling was achieved by manipulating ferroelectric domains under an in-plane magnetic field. The present work not only provides new insight into the design of molecular-based electronic ferroelectric/magnetoelectric materials but also paves the way for practical applications in a new generation of electronic devices.
由于多铁性薄膜在新一代器件中具有极其实际的用途，因此人们对其磁电耦合给予了高度重视。在此，通过简单的压印工艺制备了[(-CH)N][FeFe(dto)]（；dto = COS）薄膜。我们的实验结果表明，在50至300 K的宽温度范围内，通过Fe和Fe位点之间的电子跳跃诱导了面内铁电性。通过对化合物[(-CH)N][FeZn(dto)]（；dto = COS）的铁电观测进一步证实了这一机制，其中Fe离子被非磁性金属Zn离子取代，导致没有明显的铁电极化。然而，铁电性和磁性都与磁性Fe离子有关，这意味着中存在强磁电耦合。通过压电力显微镜（PFM），在面内磁场下通过操纵铁电畴实现了磁电耦合观测。本工作不仅为基于分子的电子铁电/磁电材料的设计提供了新见解，也为新一代电子器件的实际应用铺平了道路。
