3D Anhydrous Proton-Transporting Nanochannels Formed by Self-Assembly of Liquid Crystals Composed of a Sulfobetaine and a Sulfonic Acid

Abstract

Herein we describe anhydrous proton transportation through 3D interconnected pathways formed by self-assembled molecular complexes. A thermotropic bicontinuous cubic (Cub(bi)) phase has been successfully obtained by mixing a wedge-shaped sulfobetaine with benzenesulfonic acid in different ratios. These ionic complexes exhibit the Cub(bi) phase in a wide range of temperatures, while the single zwitterionic compound shows only a columnar hexagonal phase, and benzenesulfonic acid is nonmesomorphic. Anhydrous proton conduction on the order of 10(-4) S cm(-1) has been achieved for the mixture in the Cub(bi) phase over 100 °C, which can be useful for the development of new electrolytes for the next generation of fuel cells.

Zwitterionic liquid crystals as 1D and 3D lithium ion transport media

“…44 One of the approaches for the induction of functional thermotropic Cub bi phases is the use of two-component assemblies. [51][52][53][54] For example, we achieved 3D proton transport in the Cub bi phases formed by the complexation of zwitterionic molecules and organic acids. 52,53 The acid dissociates in the presence of zwitterions, which enables the proton transport.…”

Enhancing proton conduction via doping of supramolecular liquid crystals (4-alkoxybenzoic acids) with imidazole

“…Organic self-assemblies containing regularly arranged protonic moieties also exhibited the potential to transport protons under anhydrous conditions. Proton conduction has been achieved for smectic, columnar and cubic liquid crystals containing benzenesulfonic acid or sulfonate over 100 • C [8][9][10]. We succeeded in obtaining proton conductivity of 4.7 × 10 −3 S cm −1 at 200 • C in the layered side-chain liquid crystal polymers bearing sulfonic acids [11].…”

Lyotropic Liquid Crystals Incorporated with Different Kinds of Carbon Nanomaterials or Biomolecules

“…Among them, LLCs were a special kind of self-assemblies of amphiphilic molecules within the scope of the long-range ordered arrangement, and their unique functions cannot be replaced by other materials. For example, the LLCs can be used as mediums for various organic and inorganic reactions that can be carried out in the hydrophilic or hydrophobic domains in confined spaces of those mesophases [10][11][12][13]. Moreover, the lamellar, hexagonal and cubic phases of LLCs can also be used as soft templates to control the structure and morphology of desired composites [14].…”