Low-Surface Resistance, High-Sensitivity IPMC Sensors Enabled by Physical Deposition of AgNPs@Au Electrodes

Ionic polymer-metal composite (IPMC) integrates ionic conductivity and flexibility, exhibiting great application potential in wearable devices, bionic robots, microfluidic chips and other fields. Although the thickness of the electrode layer of IPMC fabricated by traditional physical methods is controllable, it fails to achieve high compactness, strong adhesion and low sheet resistance, resulting in performance far inferior to that of IPMCs prepared by chemical methods. To address the above issues, this work proposes a new strategy with controllable electrode layer thickness based on spraying silver nanoparticles (AgNPs) and electroplating (EP), which effectively enables the rapid construction and performance enhancement of the electrode layer. Compared with IPMCs prepared by other processes, the IPMC with sprayed AgNPs@Au electrodes shows advantages of low sheet resistance (∼0.115 Ω/□) and high sensitivity (∼8.475 mV/cm-1). Meanwhile, it maintains high stability after 1000 cyclic bends or immersion in HCl for corrosion, further demonstrating the potential application of IPMCs prepared by this process in flexible wearable sensors.