# Lithium-Ion Conduction in Liquid-Crystalline Columnar Pd(II) Nanoassemblies

## TL;DR

Researchers developed a new type of liquid crystalline material that can efficiently conduct lithium ions, potentially improving energy storage technologies.

## Contribution

The study introduces a novel approach using a bispyrazolate Pd(II) metallomesogen to create a stable, high-conductivity liquid crystalline electrolyte.

## Key findings

- Lithium ion intercalation enhances mesophase stability by forming ion–dipole interactions.
- Optimal doping achieves a Li-ion conductivity of 1.89 × 10–4 Ω–1 cm–1.
- The material operates effectively at high temperatures without flammable solvents.

## Abstract

Liquid crystalline electrolytes are emerging as a promising
class
of functional materials for energy storage applications. They offer
the ability to operate under anhydrous conditions without the presence
of acids or flammable solvents, allowing high operating temperatures.
Herein, the liquid crystalline phase of a bispyrazolate Pd­(II) metallomesogen
is used as a platform for Li-ion conduction, taking advantage of the
existence of nanochannels in the hexagonal columnar mesophase. Li-doped
liquid crystal composites have been prepared with different lithium
content, and their mesomorphic properties and ionic conductivities
were studied. It was found that the intercalation of lithium ions
between molecules does not hinder the formation of the mesophase but
rather extends the temperature range in which it is stable due to
the existence of ion–dipole interactions between the lithium
ions and the uncoordinated N-pyrazolic atoms, leading to lower melting
and higher clearing temperatures. High Li-ion conductivity was found
in the solid and liquid crystalline phases by complex impedance spectroscopy.
The optimally doped composite with an 8:2 (metallomesogen:LiTFSI)
molar ratio reaches conductivity values as high as 1.89 × 10–4 Ω–1 cm–1. The work presented is expected to pave the way for a promising
class of liquid crystalline Li-ion electrolytes based on metallomesogens.