1) Polymer Electrolyte Composite

• Ion gels are polymer electrolyte composites (PECs) based on ionic liquids (ILs) and supporting network structures.

• ILs are organic ions characterized by weak intermolecular interactions and structural asymmetries. These features reduce their tendency of crystallization, thus resulting in their low melting temperatures and high ionic conductivities at room temperature.

• PECs provide a versatile platform for wearable devices, wherein the electrical, physicochemical, and mechanical properties of the composites can be modulated depending on the IL selection and network-forming methodologies.

• Recently, more than one cross-linking mechanism has been incorporated to realize double network structures with enhanced mechanical properties.

ACS Appl. Polym. Mater. 2022, 4, 5821−5830

2) Electronic Device

• Solidified ionic liquid-based composite electrolytes, also known as ion gels, have recently attracted much interest because they possess outstanding benefits of ionic liquids such as ionic mobility, specific capacitance, chemical and electrochemical stability, and negligible vapor pressure in a solid form.

• These characteristics of the gel electrolytes allow them to be considered as attractive candidates for many applications in energy conversion/storage devices, actuators, electrochromic/ light-emitting displays, and printed electronics.

ACS Appl. Mater. Interfaces 2017, 9, 8813−8818

3) Wearable Strain Sensor

• The stretchable skin-type strain sensors were attached to various body joints (wrist and finger) and employed to detect human motion.

• The change in the relative resistance (ΔR/R0) across the specimen was monitored as tensile strains incurred by human motion were applied and released repeatedly.

• The behaviors of the undamaged and self-healed samples are not distinguishable, implying that the functionality recovery is accompanied by the restoration of the mechanical properties.

• The magnitude of the strain imposed on the device was controlled using a motorized stage, and the strain sensor was operated under small mechanical deformations.

ACS Appl. Polym. Mater. 2022, 4, 5821−5830

4) Tough Self-Healing Materials

• The composites are characterized by both IL-phobic association and crystallization. The resultant distribution of the bonding strength can result in tough networks.

• Depending on their crystallinity, the composites exhibited varying degrees of self-healing capabilities at room temperature without any external trigger (e.g., light, heat, or solvents)

• Composites also exhibited the maximal mechanical behavior, which surpassed that of previously reported room temperature self-healable PECs by orders of magnitude. The PEC was ionically conductive and was employed to fabricate self-healable strain sensors capable of monitoring human motion. 

ACS Appl. Polym. Mater. 2022, 4, 5821−5830

5) Functional Gels

• Ionogel-based Actuators

• Ionogel-based Triboelectric Nanogenerators(TENGs)