Salicylideneaniline is a Photoswitchable Ferroelectric Crystal

• Published in: Chemistry : a European journal Vol. 27; no. 60; pp. 14831 - 14835
• Main Authors: Wang, Zhong‐Xia, Huang, Chao‐Ran, Liu, Jun‐Chao, Zeng, Yu‐Ling, Xiong, Ren‐Gen
• Format: Journal Article
• Language: English
• Published: Weinheim Wiley Subscription Services, Inc 25.10.2021
• Subjects: Chemistry; Crystals; Dielectric constant; Electronic devices; Ferroelectric crystals; ferroelectric domain; Ferroelectric materials; Ferroelectricity; Ferroelectrics; Isomerization; Phase transitions; Photochromism; photoswitching; salicylideneaniline; Switching
• ISSN: 0947-6539; 1521-3765
• DOI: 10.1002/chem.202102142

Since the discovery of the first ferroelectric Rochelle salt, most ferroelectrics have been investigated showing thermally triggered symmetry‐breaking phase transition. Although photochromism arising from geometrical isomerization was reported as early as 1867, such photoswitchable ferroelectric crystals have scarcely been developed to date. Herein, we report that salicylideneaniline is a photochromic ferroelectric crystal. Upon photoirradiation, the dielectric constant shows obvious switching between high and low dielectric states, and more importantly, the ferroelectric polarization demonstrates quick and reversible switching. This work opens the gate to developing photoswitchable ferroelectrics, which holds great potential for applications in optically controlled smart devices. Salicylideneaniline has been discovered to be an organic photoswitchable ferroelectric crystal with a type of photo‐induced enol−keto structural isomerization accompanied by evident photochromism, which is different from the thermodynamic order‐disorder or displacive one. The microscopic ferroelectric polarization can be quickly and reversibly switched upon UV light irradiation, holding great promise for developing optical control of smart devices in the future.