Entropic elastic ionoelastomer with sea-island structure for ultra-high-frequency sensing

Flexible ionotronic sensors hold great promise for tactile electronics owing to their high sensitivity and mechanical compliance. However, conventional ionic conductors suffer from hysteresis and instability, which severely limit their ability to detect high-frequency vibrations. Here, we propose an ionoelastomer that possesses low hysteresis by introducing reversible sea-island structure. The structure, constructed from entropy-elastic segments of acylated poly(ethylene glycol)-b-poly(propylene glycol)-b-poly(ethylene glycol) (PF127-DA), can rapidly respond to external mechanical vibrations, enabling high-frequency sensing. The ionoelastomer-based sensor with dual-microcone structure achieves a maximum sensitivity of 590.2 kPa −1 and a rapid response/recovery time of 0.5/0.5 ms, allowing it to detect vibrations up to 1 kHz. Additionally, the sensor has been applied to audio recognition and an integrated sensor array, demonstrating reliable signal responses in interactive electronics and showing great potential for future interactive and force monitoring applications.