CB Nanoparticles Optimized 3D Wearable Graphene Multifunctional Piezoresistive Sensor Framed by Loofah Sponge

Three-dimensional (3D) wearable piezoresistive sensors with excellent performance are urgently needed in many emerging fields. Herein, a hybrid piezoresistive sensor with 3D structure, which is framed by loofah sponge and coated with reduced graphene oxide modified with carbon black nanoparticles (rGO-CB@LS), was obtained via a facile solvothermal method. The ingenious use of loofah sponge (LS) provides a 3D highly ordered structure with excellent flexibility for the hybrid sensor, which assists the sensor free from the dependence on an organic substrate and eliminates the pollution to the environment. While the addition of carbon black (CB) nanoparticles can reduce the contact resistance between rGO sheets, improve the conductivity and sensitivity effectively, and shorten the response/recovery time of the sensor. An ultralight piezoresistive sensor, which is low cost and environmentally friendly, was obtained under the synergy of LS and rGO-CB, accompanied by high sensitivity and good stability. This novel sensor also exhibits excellent performance in detecting tiny and big human activities, demonstrating its great potential for a new generation of 3D wearable sensors.