High-performance and superhydrophobic piezoresistive pressure sensor based on mountain ridge-like microstructure by silver nanoparticles and reduced graphene oxide

Ingenious microstructure design is crucial for piezoresistive pressure sensor to achieve excellent sensing per-formances and water repellency. Herein, we propose a new strategy to prepare high-performance poly-dimethylsiloxane (PDMS) sponge-based piezoresistive pressure sensor with superhydrophobicity. The silver nanoparticles and reduced graphene oxide on the skeleton surface of PDMS sponge jointly constructed mountain ridge-like microstructure and endowed the sensor with conductive network. The sensor exhibited high sensi-tivity, wide detection range, fast response and exceptional repeatability (4,000 loading-unloading cycles) and was applied for detecting human motions and daily scenarios. Owing to the hierarchical microstructure and the surface modification by 1H,1H,2H,2H-perfluorooctyltriethoxysilane, the sensor showed a high water contact angle of 156, and the response signal kept stable even being sprayed by water. The prepared high-performance and superhydrophobic piezoresistive pressure sensor in this work has great potential in wearable electronics, healthcare monitoring and smart robot.