In-Plane Ferroelectricity in Thin Flakes of Van der Waals Hybrid Perovskite

Lu You; Fucai Liu; Hongsen Li; Yuzhong Hu; Shuang Zhou; Lei Chang; Yang Zhou; Qundong Fu; Guoliang Yuan; Shuai Dong; Hong Jin Fan; Alexei Gruverman; Zheng Liu; Junling Wang

doi:10.1002/adma.201803249

In-Plane Ferroelectricity in Thin Flakes of Van der Waals Hybrid Perovskite

Adv Mater. 2018 Dec;30(51):e1803249. doi: 10.1002/adma.201803249. Epub 2018 Oct 17.

Authors

Lu You¹, Fucai Liu^{2

3}, Hongsen Li^{1

4}, Yuzhong Hu⁵, Shuang Zhou^{1

6}, Lei Chang¹, Yang Zhou¹, Qundong Fu³, Guoliang Yuan⁷, Shuai Dong⁸, Hong Jin Fan⁵, Alexei Gruverman⁹, Zheng Liu³, Junling Wang^{1

10}

Affiliations

¹ School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
² School of Optoelectronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, 610054, P. R. China.
³ Centre for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore.
⁴ School of Chemistry and Chemical Engineering, Shanghai University of Engineering Science, Shanghai, 201620, P. R. China.
⁵ School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore, 637371, Singapore.
⁶ School of Science, Nanjing University of Posts and Telecommunications, Nanjing, 210023, P. R. China.
⁷ School of Materials Science and Engineering, Nanjing University of Science and Technology, Nanjing, 210094, P. R. China.
⁸ School of Physics, Southeast University, Nanjing, 211189, P. R. China.
⁹ Department of Physics and Astronomy, University of Nebraska-Lincoln, Nebraska, 68588, USA.
¹⁰ Academy for Advanced Interdisciplinary Studies and Department of Physics, Southern University of Science and Technology, Shenzhen, 518055, P. R. China.

PMID: 30334281
DOI: 10.1002/adma.201803249

Abstract

Collective ferroic orders in van der Waals (vdW) crystals are receiving increasing attention in 2D materials research. The interplay between spatial quantum confinement and long-range cooperative phenomena not only broadens the horizon of fundamental physics, but also enables new device paradigms and functionalities built upon vdW heterostructures. Here, the in-plane ferroelectric properties in thin flakes of vdW hybrid perovskite bis(benzylammonium) lead tetrachloride are studied. The ordering of electric dipoles along the layer plane circumvents the depolarization field and preserves the ferroelectricity down to one unit-cell thickness or two vdW layers at room temperature. The superior performance of the electromechanical energy conversion is demonstrated by exploiting its in-plane piezoelectricity. The successful isolation of ferroelectric order in atomically thin vdW hybrid perovskite paves the way for nonvolatile flexible electronic devices with the cross-coupling between strain, charge polarization, and valley degrees of freedom.

Keywords: 2D materials; ferroelectricity; flexible electromechanical devices; hybrid perovskite; piezoresponse force microscopy.

Abstract

Grants and funding