Ferroelectric Polarization Switching Dynamics and Domain Growth of Triglycine Sulfate and Imidazolium Perchlorate

Abstract

The weak bond energy and large anisotropic domain wall energy induce many special characteristics of the domain nucleation, growth, and polarization switch in triglycine sulfate (TGS) and imidazolium perchlorate (IM), two typical molecular ferroelectrics. Their domain nucleation and polarization switch are rather slower than those of conventional oxide ferroelectrics, which may be due to the weaker bond energy of hydrogen bond or van der Waals bond than that of ionic bond. These chemical bonds dominate the elastic energy, with the latter being an important component of domain wall energy and playing an important role in domain nucleation and domain growth. The ratio of anisotropic domain wall energy to Gibbs free energy is large in TGS and IM, which allows a favorable domain shape and a special domain evolution under a certain electric field. Therefore, this study not only sheds light on the physical nature but also indicates the application direction for molecular ferroelectrics.

Ferroelectric Behavior of an Octahedral Metal‐Ligand Cage and Its 2D‐Connected Cage Framework

“…As a result, the supramolecular ferroelectrics based on weak interactions may often exhibit higher P r than P s due to the slower switching of polarization in comparison with those of the conventional oxide ferroelectrics. [30] In addition to the PÀ E hysteresis curves, capacitance vs. voltage (CÀ V) curves were also measured for both these assemblies. The CÀ V characteristics were measured by sweeping the voltages up and down between 0 and � 60 V and 0 and � 100 V, respectively, on the crystals of 1 and 2 (Figures 3c and 3d).…”

“…Normally, the elastic energy of the bonds plays a vital role in domain evolution and the field dependent polarization switch. As a result, the supramolecular ferroelectrics based on weak interactions may often exhibit higher P r than P s due to the slower switching of polarization in comparison with those of the conventional oxide ferroelectrics …”

Designed Giant Room‐Temperature Electrocaloric Effects in Metal‐Free Organic Perovskite [MDABCO](NH4)I3 by Phase–Field Simulations

“…The abundant organic components soften the compounds, which assists in the growth of high‐quality thin films. [ 21 ] In the last decade, molecular ferroelectric thin films have gradually attracted the attention of researchers and been investigated in broad fields, such as ferroelectrics, [ 47,48 ] piezoelectrics, [ 49,50 ] pyroelectricity, [ 51,52 ] magnetoelectric coupling, [ 53 ] electromechanical coupling, [ 54 ] polarization switching, [ 55,56 ] and perovskite solar cells. [ 57 ] One merit of low‐molecular mass organic compounds is their applicability with a solution and/or their drying processes.…”

“…[ 57 ] One merit of low‐molecular mass organic compounds is their applicability with a solution and/or their drying processes. [ 56 ] Therefore, the molecular ferroelectric thin films can be prepared by a simple drop‐casting method with slow evaporation technology, and the solution process makes it have large‐area coverage and good uniformity. [ 47,50 ] The simple stamping process [ 53 ] or an easy processing spinning method [ 49 ] can also be employed to fabricate molecular ferroelectric thin films.…”

A 3D-printed molecular ferroelectric metamaterial

“…Here, we unravel a printable mechanical metamaterial of imidazolium perchlorate (ImClO 4 ) (2,22,23), a transparent molecular ferroelectric with superior electromechanical coupling and reprogrammable stiffness. We propose a continuous rapid 3D printing technique which can reduce the manufacturing time of ferroelectrics from hours down to minutes.…”