This paper describes the preparation, physical properties, and electric bending actuation of a new class of active materials—ionic liquid crystal elastomers (iLCEs). It is demonstrated that iLCEs can be actuated by low‐frequency AC or DC voltages of less than 1 V. The bending strains of the unoptimized first iLCEs are already comparable to the well‐developed ionic electroactive polymers. Additionally, iLCEs exhibit several novel and superior features, such as the alignment that increases the performance of actuation, the possibility of preprogrammed actuation patterns at the level of the cross‐linking process, and dual (thermal and electric) actuations in hybrid samples. Since liquid crystal elastomers are also sensitive to magnetic fields and can also be light sensitive, iLCEs have far‐reaching potentials toward multiresponsive actuations that may have so far unmatched properties in soft robotics, sensing, and biomedical applications.

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The present article entails the generation of flexoelectricity during cantilever bending of a solid polymer electrolyte membrane (PEM), composed of poly­(ethylene glycol) diacrylate (PEGDA) precursor and ionic liquid (hexylmethyl­imidazolium hexafluorophosphate). The effects of thiosiloxane modification of PEGDA precursor on glass transition, ionic conductivity, and flexoelectric performance have been explored as a function of PEM composition. The glass transition temperature (T g) of the PEM declines with increasing thiosiloxane amount in the PEGDA co-network, while the ionic conductivity improves. The PEM/compliant carbonaceous electrodes assemblies were assembled to determine the flexoelectric coefficients by monitoring electrical voltage/current outputs for various PEM compositions under the intermittent square-wave and dynamic oscillatory sine-wave deformation modes. Of particular interest is that the room temperature flexoelectric coefficient exhibits strong frequency dependence in the vicinity of 0.01–10 Hz, suggesting that ion polarization and ion transport through the ion-dipole complexed networks can still be affected by the mobile side chain branches even in the elastic regime of the covalently bonded PEGDA network. The in-depth understanding of the effect of thiosiloxane side chain on flexoelectricity generation is anticipated to have impact on the development of mechano­electrical energy conversion devices for energy harvesting applications from natural and dynamical environment.

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for sub-millisecond electro-optic modulators [13][14][15] and display panels. [16][17][18] However, until recently ferroelectricity was observed only in smectic [19] and columnar [20] phases, which are fluid only in two and one dimension, respectively. Due to their piezoelectricity, they deform mechanically during electric switching, eventually leading to permanent defects in the layers or columns. [21] 3D nematic fluids with large molecular dipole moments along the long axis of rod-shaped molecules were predicted to be ferroelectric already in the 1910s by Debye [22] and Born; [23] similar predictions were made later for disc- [24] and pearshaped liquid crystals (LCs). [25] In 2017, over a century after Debye and Born's arguments, Nishikawa et al. [26] found the first evidence of ferroelectric nematic phase (N F ) in a strongly polar 1,3-dioxanebased rod-shaped material, DIO. That same year, Mandle et al. [27,28] reported an N−N transition in another highly polar nematic material, 4-[(4-nitrophenoxy)carbonyl]phenyl2,4-dimethoxybenzoate (RM734). The lower temperature phase was later proposed to be a splay nematic, [29] with the splay deformation being the result of polar molecular ordering. [30] Very recently, Chen et al., argued that this polar ordering does not couple to a splay deformation, but instead, the lower temperature phase is a uniform ferroelectric nematic with a spontaneous polarization as high as 6 µC cm −2 . [31] The large polarization values up to 4-6 µC cm −2 measured by Nishikawa et al. [26] on DIO and Chen et al. [31] on RM734 indicate strong polar order, which is the primary order parameter, similarly to the SmAP and SmCP subphases of bent-core smectic LCs. [32,33] The large ferroelectric polarization and dielectric constant, coupled with sub-millisecond switching, offer potential applications such as high-power super capacitors and low voltage driven fast electro-optical devices. The electro-optical properties of RM734 were recently shown to depend strongly on the surface treatments of the samples, [34,35] namely that the polarity of surface anchoring may couple to the bulk polar order parameter and lead to oppositely twisted domains. To obtain a uniform texture, one needs to bias the twist by adding chiral dopants to the system. [40] The presence of molecular chirality in liquid crystals usually leads to a helical director structure. [36,37] In conventional nematic materials the twist elastic constant K 22 is smaller than the splay (K 11 ) and bend (K 33 ) elastic constants and the director n is The recently discovered ferroelectric nematic (N F ) liquid crystals (LCs) with over 0.04 C m −2 ferroelectric polarization and 10 4 relative dielectric constants, coupled with sub-millisecond switching, offer potential applications in highpower super capacitors and low voltage driven fast electro-optical devices. This paper presents electrical, optical, and electro-optical studies of a ferroelectric nematic LC material doped with commercially available chiral dopants. While the N F phase of the undo...