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Updated: Dec 20, 2025
11:04
Synthesis of Ionic Liquid Based Electrolytes, Assembly of Li-ion Batteries, and Measurements of Performance at High Temperature
Published on: December 20, 2016
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Structure Effects on the Ionicity of Protic Ionic Liquids.
Sarah K Mann1, Steven P Brown1, Douglas R MacFarlane2
1Department of Physics, University of Warwick, Coventry, CV4 7AL, U.K.
Summary
This study characterizes 16 protic ionic liquids (PILs), revealing that primary amines yield greater proton transfer than tertiary amines. Understanding PIL structure-property relationships aids in designing advanced ionic liquids for diverse applications.
Area of Science:
- Materials Science
- Physical Chemistry
Background:
- Protic ionic liquids (PILs) are synthesized via amine-acid neutralization.
- Characterizing PILs is crucial for understanding their behavior and optimizing applications.
Purpose of the Study:
- To synthesize and characterize 16 protic ionic liquids (PILs).
- To investigate the relationship between PIL structure and properties, including proton transfer, ionicity, and transport characteristics.
- To provide insights for designing PILs with tailored properties.
Main Methods:
- Synthesis of PILs through neutralization of primary/tertiary amines with carboxylic acids.
- Characterization using differential scanning calorimetry.
- Measurement of transport properties: viscosity, conductivity, and diffusivity.
- Analysis using the (fractional) Walden rule and pulsed-field gradient spin-echo (PGSE) NMR.
Main Results:
- Greater proton transfer observed in primary amine-based PILs compared to tertiary amine-based PILs.
- Enhanced proton transfer in tertiary amine PILs achieved through hydroxyl groups or solvent mixtures.
- Ionicity decreases with increased alkyl chain length and branching in cations and anions.
- Transport properties analyzed for deviations from ideal behavior using the Walden rule.
Conclusions:
- Structure significantly influences protic ionic liquid properties.
- Tailoring PIL structure, such as amine type and solvation environment, affects proton transfer and ionicity.
- Findings contribute to the rational design of PILs for specific applications.
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