Diisopropylammonium Bromide Based Two-Dimensional Ferroelectric Monolayer Molecular Crystal with Large In-Plane Spontaneous Polarization

Authors

Liang Ma, University of Nebraska-Lincoln
Yinglu Jia, University of Nebraska-LincolnFollow
Stephen Ducharme, University of Nebraska - LincolnFollow
Jinlan Wang, University of Nebraska-Lincoln
Xiao Cheng Zeng, University of Nebraska-LincolnFollow

ORCID IDs

Liang Ma 0000-0003-4747-613X

Jinlan Wang 0000-0002-4529-874X

Xiao Cheng Zeng 0000-0003-4672-8585

Date of this Version

2019

Citation

Published in Journal of the American Chemical Society 141 (2019), pp 1452−1456.

DOI: 10.1021/jacs.8b12102

Comments

Copyright © 2019 American Chemical Society. Used by permission.

Abstract

In light of their easy processing, light weight and mechanical flexibility, ferroelectric molecular crystal with large spontaneous polarization (P_s) is highly desired for many advanced applications. Herein, we report the first theoretical study of two-dimensional (2D) ferroelectric molecular crystals via ab initio calculations. Specifically, we show that diisopropylammonium bromide (DIPAB) based 2D ferroelectric monolayer molecular crystal with large in-plane P_s of ∼1.5 × 10⁻⁶ μC cm⁻¹ can be achieved by slicing the bulk DIPAB along a specific plane while keeping the space group unchanged. The important roles of hydrogen bonds are also identified. Ab initio molecular dynamics simulations indicate that, with the support of a graphene substrate, the ferroelectric order of 2D DIPAB monolayer can be retained at room temperature. Lastly, we show that several other diisopropylammonium halide molecular crystals can also be used to achieve 2D all-organic ferroelectric monolayer singular molecular crystal with large in-plane P_s.