Resistive pressure sensor for high-sensitivity e-skin based on porous sponge dip-coated CB/MWCNTs/SR conductive composites

Three-dimensional (3D) porous conductive sponge with excellent electrical and mechanical properties has drawn great attention for developing wearable electronic skin (e-skin). Here, we reported a simple, practical and efficient 'dip-coating' technique to fabricate a resistive pressure sensor with excellent elasticity, high pressure sensitivity of 0.35 kPa −1 , long-term reproducibility and durability (∼2000 cycles), fast response time (∼45 ms), based on homogenous 3D hybrid conductive network of carbon black (CB)/multi-walled carbon nanotube (MWCNTs)/silicon rubber (SR) nanocomposites layer-by-layer dip-coated on porous polyurethane (PU) sponge. The good electrical and mechanical performances are achieved using the three-dimensional porous microstructure of polyurethane sponge and the synergistic conductive network of CB/MWCNTs. The fabricated sensor can be used to detect a small-scale human motion, including swallowing, coughing, breathing, clenching, screwing and exercising. The CB/MWCNTs/SR/PU based resistive pressure sensor with high performance and a simple fabrication process will provide new insight into the application flexible wearable electronic skin for real-time health monitoring, human activity monitoring and human-machine interfaces.