Dually cross-linked single network poly(ionic liquid)/ionic liquid ionogels for a flexible strain-humidity bimodal...

Area of Science:

• Materials Science
• Polymer Chemistry
• Electrochemical Engineering

Background:

• Gel electrolytes are crucial for flexible electronics due to high ionic conductivity and stretchability.
• Existing gel electrolytes face limitations in mechanical strength, fatigue resistance, and environmental adaptability.
• These limitations hinder the widespread application of gel-based flexible electronic devices.

Purpose of the Study:

• To synthesize a novel polymerizable ionic liquid monomer, [SBMA][AA].
• To prepare a dually cross-linked single network poly(ionic liquid)/ionic liquid (DCSN PIL/IL) ionogel.
• To evaluate the ionogel's potential for flexible electronics, particularly as strain and humidity sensors.

Main Methods:

• Synthesized [SBMA][AA] by combining zwitterionic sulfobetaine methacrylate and acrylic acid.
• Prepared the DCSN PIL/IL ionogel via one-step photopolymerization of [SBMA][AA] in 1-ethyl-3-methylimidazolium dicyanoamide ([EmIm][DCA]).
• Investigated the ionogel's mechanical properties, ionic conductivity, adhesion, and electromechanical response.

Main Results:

• The DCSN PIL/IL ionogel exhibited superior mechanical properties and fatigue resistance due to synergistic dual cross-linking.
• High ionic conductivity and excellent environmental adaptability were achieved by incorporating [EmIm][DCA].
• The ionogel demonstrated strong adhesion and was effective as a strain sensor for human activities and a humidity sensor.

Conclusions:

• The developed DCSN PIL/IL ionogel overcomes limitations of traditional gel electrolytes.
• Its unique properties make it suitable for advanced flexible electronics, including bimodal strain-humidity sensors.
• This ionogel presents significant potential for wearable devices and environmental monitoring applications.