A Molecular Ferroelectric Showing Room-Temperature Record-Fast Switching of Spontaneous Polarization

Angew Chem Int Ed Engl. 2018 Jul 26;57(31):9833-9837. doi: 10.1002/anie.201805776. Epub 2018 Jul 9.

Abstract

Fast switching of spontaneous polarization (Ps ) is one of the most essential requirements for ferroelectrics used in the field of data storage. However, in contrast to inorganic counterparts, the low operating frequency (<500 Hz) for molecular ferroelectrics severely hinders their large-scale applications. Herein, for the first time, we achieved the room-temperature fastest switching of the Ps in a new molecular ferroelectric, N-methylmorpholinium trinitrophenolate (1), which displays notable ferroelectricity (Ps =3.2 μc cm-2 ). Strikingly, electric polarizations of 1 have been switched under a record-high frequency of 263 kHz, and this performance remains stable without any obvious fatigue after ca. 2×105 switching cycles. To our knowledge, 1 is the first organic ferroelectric to switch polarization at such a high operating frequency, exceeding the majority of organic ferroelectrics, which opens up new possibilities for its potential in the field of non-volatile memory.

Keywords: ferroelectricity; molecular ferroelectrics; organic ferroelectrics; phase transition; polarization switching.