Vat Photopolymerization 3D Printing of High-Performance Ionic Organogel for Multifunctional Sensors

Abstract

Ionic gels present a promising solution to meet the growing demand for stretchable and conductive materials in wearable and flexible devices. Compared to ionic hydrogels, which exhibit poor thermal and electrical stability, ionic organogels demonstrate significant potential due to their superior performance characteristics. However, the fabrication of ionic organogels that exhibit high mechanical properties, transparency, and stability remains a significant challenge. In this paper, we report the fabrication of an ionic organogel using vat photopolymerization 3D printing with Projection Micro-Stereolithography technology under mild conditions. The 3D-printed ionic organogel exhibits outstanding transparency (93.81% in the range of 400-800nm), high stretchability (elongation at break of 2782%), tunable mechanical properties, excellent ionic conductivity, electrical stability with a high decomposition voltage of 4V, and thermal stability up to 300°C. The strain sensor based on the ionic organogel is capable of monitoring human movement, including both large-scale movements and subtle signals, with high sensitivity and extreme-temperature tolerance. In addition, the ionic organogel-based pressure and temperature sensor with dual functionality demonstrates excellent temperature and pressure sensing capabilities, even at extreme temperatures up to 100°C (boiling point of water). Thus, the as-fabricated ionic organogel presents an excellent choice of material for wearable and flexible devices, particularly for applications operating in harsh and extreme-temperature environments.