Ionic Polymer Sensors with High Stability and Fast Preparation Process Based on Spraying Coating and Ionic Liquid Immersion

Ionic polymer sensors (IPS) can replicate the topological structures of human skin based on the ion migration mechanism, which has great application potential in the fields of medical monitoring and electronic skins. The existing piezoelectric IPS are usually prepared through chemical methods and utilize cations and water as the electrolyte, which has two challenges: a slow preparation process and solvent volatilization. In this article, we proposed a fast method to prepare piezoelectric IPS by integrating spraying and electrodepositing Au processes. Meanwhile, the method of heating in ionic liquid solution was adopted to effectively enhance the long-term stability of IPS. Compared with the traditional IPS based on Na⁺, the sensitivity of the prepared IPS to humidity was decreased by 1531%, increasing the environmental stability. Besides, the signal amplitude of the prepared IPS showed no decay caused by the volatilization of the electrolyte during 12 days of exposure, exhibiting excellent long-time stability. Moreover, the prepared IPS was integrated into a wearable sensing glove, which realized the functions of gesture recognition, pulse measurement, and grip force monitoring and showed good application potential in the field of wearable sensing.