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

Abstract

Fast switching of spontaneous polarization (P ) 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 P in a new molecular ferroelectric, N-methylmorpholinium trinitrophenolate (1), which displays notable ferroelectricity (P =3.2 μc cm ). 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. 2×10 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.

Ferroelectric Metal–Organic Framework as a Host Material for Sulfur to Alleviate the Shuttle Effect of Lithium–Sulfur Battery

“…[9][10][11] Ferroelectric materials usually exhibit excellent ferroelectric, piezoelectric, ferroelastic and other distinctivep hysicalp roperties, such as colossal magnetoresistancea nd high dielectric constant properties, etc.,w hich can be widely used as photoelectric and energy storage devices. [12][13][14] Among these attractive properties, the spontaneousp olarizations witching behavior of ferroelectrics under the irritation of an externale lectric field is extremely important in theoretical research and application fields. [15] Recently,t he ceramic ferroelectric has been used as additives to sulfurc athodes becauseo ft he internal electric field inducedb ys pontaneous polarization to trap polysulfides.…”

Molecular rotors with designed polar rotating groups possess mechanics-controllable wide-range rotational speed

“…For example, the required range of controllable energy barrier at 300 K is 75 times the one at 4 K. Consequently, working temperature of molecular rotors is largely limited by its controllable range of energy barrier. Considering the demand of utilizing molecular rotors at room temperature [28][29][30] , there is a need to explore means to control energy barrier continuously and effectively.…”

High‐Temperature Reversible Phase‐Transition Behavior, Switchable Dielectric and Second Harmonic Generation Response of Two Homochiral Crown Ether Clathrates

“…As molecular reversible phase transition materials were continuously discovered, higherr equirementsa re focusedo nt he exploration of high molecular phase transition temperature and multiple functional molecular materials (such as SHG responses, chirality) because of their excellentp erformance and practicality.I nspiringly,anew class of compounds, namely the crown ether clathrates has attracted great attentioni nr ecent years. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] These clathrates tend to form a" stator-rotor" configuration with protonated organic amine cations and deprotonated inorganic acid anions. [17][18][19][20][21] When the temperature changes,t he protonated organic aminec ation often acts as a rotor and undergoes slightt orsion or order-disorder change, sometimes the crown ether rings may also undergo order-disorder rotation, therebyi nducing the reversible phase transition.…”

“…As molecular reversible phase transition materials were continuously discovered, higher requirements are focused on the exploration of high molecular phase transition temperature and multiple functional molecular materials (such as SHG responses, chirality) because of their excellent performance and practicality. Inspiringly, a new class of compounds, namely the crown ether clathrates has attracted great attention in recent years . These clathrates tend to form a “stator‐rotor” configuration with protonated organic amine cations and deprotonated inorganic acid anions .…”