Unlocking Intrinsic Conductive Dynamics of Ionogel Microneedle Arrays as Wearable Electronics for Intelligent Fire Safety

DOI:  10.1007/s42765-023-00344-x

Keywords: Multifunctional ionogel, Intrinsic conductive dynamics, Bionic microneedle array, Intelligent safety system, pressure, Materials Science

Abstract: 

Ionogels have enabled flexible electronic devices for wide-ranging innovative applications in wearable electronics, soft robotics, and intelligent systems. Ionogels for flexible electronics need to essentially tolerate stress, temperature, humidity, and solvents that may cause their electrical conductivity, structural stability, processing compatibility and sensibility failure. Herein, we developed a novel in-situ photopolymerization protocol to fabricate intrinsically conductive, self-gated ionogels via ion-restriction dual effects. Highly sensitive and intelligent safety sensors with tunable stretchability, robust chemical stability, favorable printability, and complete recyclability, are programmed from defined microneedle arrays printed by the intrinsically conductive ionogel. Ultrahigh elasticity (similar to 794% elongation), high compression tolerance (similar to 90% deformation), improved mechanical strength (tensile and compressive strength of similar to 2.0 MPa and similar to 16.3 MPa, respectively) and remarkable transparency (> 91.1% transmittance), as well as high-temperature sensitivity (- 2.07% degrees C-1) and a wide working range (- 40 to 200 degrees C) can be achieved. In particular, the intrinsic sensing mechanisms of ion-restriction dual effects are unlocked based on DFT calculations and MD simulations, and operando temperature-dependent FTIR, and Raman technologies. Moreover, the real-time intelligent monitoring systems toward physical signals and precise temperature based on the microneedle array-structures sensors are also presented and demonstrate great potential applications for extreme environments, e.g., fire, deep-sea or aerospace.