Tuning the Ferroelectric Properties of Trialkylbenzene‐1,3,5‐tricarboxamide (BTA)

Abstract

This study demonstrates how simple structural modification of a prototypical organic ferroelectric molecule can be used to tune its key ferroelectric properties. In particular, it is found that shortening the alkyl chain length of trialkylbenzene-1,3,5-tricarboxamide (BTA) from C18H37 to C6H13 causes an increase in depolarization activation energy (approximate to 1.1-1.55 eV), coercive field (approximate to 25-40 V mu m(-1)), and remnant polarization (approximate to 20-70 mC m(-2)). As the polarization enhancement far exceeds the geometrically expected factor, these observations are attributed to an increase in the intercolumnar interaction. The combination of the mentioned characteristics results in a record polarization retention time of close to three months at room temperature for capacitor devices of the material having the shortest alkyl chain. The long retention and the remnant polarization that is as high as that of P(VDF:TrFE) distinguish the BTA-C6 material from other small molecular organic ferroelectrics and make it a perspective choice for applications that require cheap, flexible, and lightweight ferroelectrics.<p>Funding Agencies|NWO Nano program; Vetenskapsradet; Swedish Government Strategic Research Area in Materials Science on Functional Materials at the Linkping University (Faculty Grant SFO Mat LiU) [2009 00971]</p

Negative piezoelectric effect in an organic supramolecular ferroelectric

“…31 Differently to the conventional liquidcrystalline materials used for electrooptical applications, BTA maintains its macrodipole orientation at zero external field due to p-p stacking and hydrogen-bonding, which allows it to keep the polarization for up to 10 years at room temperature. [31][32][33] The overall performance of thin-film BTA capacitor devices is comparable to devices based on P(VDF-TrFE), additionally offering some advantages like lower processing temperatures, easy chemical tuning and a wider operational temperature window. 31,34,35 In this study we present interferometrically measured converse piezoelectric response in solution-processed thin-film BTA capacitor devices.…”

“…[31][32][33] The overall performance of thin-film BTA capacitor devices is comparable to devices based on P(VDF-TrFE), additionally offering some advantages like lower processing temperatures, easy chemical tuning and a wider operational temperature window. 31,34,35 In this study we present interferometrically measured converse piezoelectric response in solution-processed thin-film BTA capacitor devices. Using density functional theory (DFT) and molecular dynamics (MD) simulations, we explain the origin of the observed anomalous negative piezoelectric effect in BTA from the microscopic and macroscopic perspective.…”

C3 Symmetric Hexaphenyltriphenylenehexamide: Molecular Design of Fluorescent Ferroelectrics

“…Collective inversion of intermolecular N‐H•••O=C hydrogen bonds in the molecular assembly of 6TP in the LC phase was achieved to induce significant P ‐ E hysteresis. Selection of the central π core and further optimization of the arrangement of amide groups, such as with regard to the substitution fashion and length of alkyl chains, would enable the further development of multifunctional ferroelectric organic materials, which is under investigation in our laboratory.…”

Ferroelectrically Switching Helical Columnar Assembly Comprising Cisoid Conformers of a 1,2,3‐Triazole‐based Liquid Crystal

“…With the increase in the E‐field strength, P s increases gradually and finally reaches a maximum of approximately 1.62 μC cm −2 (1.37 μC cm −2 ) near 40 V μm −1 at 105 °C (115 °C; Figure S5 a). This E‐field‐dependent polarization behavior is a typical characteristic of the polar switching phenomenon . To confirm that this P s value originates from molecular polarization, we calculated the theoretical P s based on the XRD data and dipole moment (μ 0 =4.55 Debye) of a 1,2,3‐triazolyl unit .…”