Mixing divalent ionic liquids: effects of charge and side-chains

Area of Science:

• Materials Science
• Physical Chemistry
• Chemical Engineering

Background:

• Ionic liquids (ILs) are versatile materials with tunable properties.
• Divalent ILs offer unique characteristics due to their multiple charge centers.
• Understanding IL mixing behavior is crucial for their application.

Purpose of the Study:

• To synthesize and characterize novel divalent ionic liquids.
• To investigate the impact of cation structure and divalency on IL properties.
• To explore the thermodynamics of mixing divalent and monovalent ILs.

Main Methods:

• Synthesis of novel divalent ionic liquids with bis(trifluoromethylsulfonyl)imide anions.
• Measurement of physical properties including thermal stability and viscosity.
• Thermodynamic analysis of mixtures containing divalent and monovalent ILs.

Main Results:

• Shortening the spacer in divalent ILs reduced thermal stability and increased viscosity.
• Mixtures of divalent and monovalent ILs exhibited significant deviations from ideal mixing.
• Mixing non-ideality was influenced by cation side-chain characteristics and charge density.

Conclusions:

• The design of cation side-chains significantly impacts the properties and mixing behavior of divalent ILs.
• Divalent ILs present complex mixing thermodynamics influenced by structural and charge factors.
• Further research into IL mixtures can lead to tailored material design for specific applications.