Ion-Pair-Tuned Ionogels for Broad-Range Linear Pressure Sensing

Abstract

Ionogels combine the mechanical softness of polymers with the ionic conductivity and nonvolatility of ionic liquids, offering a versatile platform for wearable electronics and sensing applications. In particular, their high deformability and ionic responsiveness make them attractive dielectric materials for capacitive pressure sensors. However, conventional ionogels often exhibit dielectric saturation and nonlinear responses at elevated pressures, limiting their usable operating range. Here, we report ion-pair-tuned ionogels that balance ionic mobility and polarizability to mitigate dielectric saturation and broaden the linear sensing range up to the megapascal level while maintaining high sensitivity. To validate broad-range functionality—from subtle physiological pressures to large mechanical loads—we integrate the ionogels into intraocular pressure sensors and prosthetic interface monitors, representing low- and high-pressure regimes. These demonstrations establish ion-pair tuning as an effective strategy for achieving broad linear sensing performance in wearable pressure sensors.