Enhanced Carbon Nanotube Ionogels for High-Performance Wireless Strain Sensing

Ionogels, as emerging stretchable conductor materials, have garnered significant attention for their potential applications in flexible electronics, particularly in wearable strain sensors. However, a persistent challenge in optimizing ionogels lies in achieving a balance between enhanced mechanical properties and electrical conductivity. In this study, we successfully addressed this challenge by incorporating carbon nanotubes (CNTs) into ionogels, achieving a simultaneous improvement in the electrical conductivity (2.67 mS/cm) and mechanical properties (400.83 kPa). The CNTs served dual purposes, acting as a continuous conductive pathway to facilitate electrical signal transmission and as reinforcing nanotubes to bolster the mechanical robustness of the ionogels. Additionally, the polymer network, composed of acrylic acid (AA) and 2-hydroxyethyl acrylate (HEA), established a purely physical cross-linking network characterized by dense hydrogen bonding, which ensured sufficient toughness within the ionogels. Notably, the assembled ionogels, when utilized as wireless strain sensors, demonstrated exceptional sensitivity in detecting subtle finger movements, with the CNTs significantly amplifying the electrical response. This work provides new insights into the integration of carbon nanotubes in ionogels, expanding their applications and pioneering a fresh approach to functionalized ionogel design.