ABSTRACT Two series of lithium ion liquid-crystalline composites (LCCs) containing metal-organic frame (MOF) materials were fabricated via a self-assembly process by use of poly(4-styrenesulfonic acid) lithium polymers, a cholesteryl-based liquid-crystalline monomer with terminal sulphonic acid group, and Fe-MIL-53_NH2. The chemical structure, chiral smectic C mesophase and ferroelectric property of the LCCs were characterised by various instruments, and the effect of liquid crystal monomer and lithium polymers on the ferroelectric property were investigated. The cholesteryl-based liquid crystal monomer presents a dominant role in the ferroelectric property of the LCCs, in which the asymmetric carbon atoms are responsible for the spontaneous polarisation. For the LCCs, the mechanical properties and porous loading characteristics of liquid crystal polymer are improved by the MOF materials, and the lithium-ion polymer connects the liquid crystal monomer with the MOF by ionic bond and improves the polarity of the material. When the electric field changed from −10 V and 10 V, the maximum residual polarisation strength (Pr) of the LCCs reached 74.82 nC/cm2. Because the LCCs showed excellent ferroelectric and mechanical properties, it has some potentials of application in the field of ferroelectric materials.
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