Electrospun (K,Na)NbO₃ Piezoceramic Fibers for Self‐Powered Tactile Sensing Application

Abstract

This study investigates the electrical properties of electrospun ceramic fiber mats based on potassium sodium niobate ((K,Na)NbO3;KNN) for potential applications in soft‐robotic tactile sensors. The rheological studies of electrospinning solutions exhibit shear thinning behavior, with a viscosity plateau between shear rates of 1–100 s−1. The thermal decomposition behavior of the KNN samples is analyzed using thermogravimetric analysis; the samples show multistep decomposition processes leading into a phase pure perovskite structure. For the electrospun KNN fiber mats, the electrical characterization reveals ferroelectric hysteresis loops with a high leakage current of ≈270 nA at 20 kV cm−1 and switching current behavior. The ferroelectric results indicate that a full polarization of KNN‐fiber mats is not possible due to their electrical breakdown at high electrical fields. The integration of KNN short fibers into a soft‐bending actuator demonstrates successful tactile sensing capabilities. The experimental findings reported here highlight the potential of electrospun KNN fiber mats for flexible and autonomous device applications in soft robotics.