Compressible and sensitive aerogels derived from graphene/waste paper for wearable pressure sensor

Biomass-derived 3D and porous conductive aerogels have been considered as potential environmentally friendly material for wearable pressure sensors. However, the development of a simple strategy for the fabrication of biomass-derived aerogels with the properties of wide-sensing range, high sensitivity, and low detection is still significantly challenging. Here, graphene was incorporated into waste paper to prepare graphene-coated waste paper aerogel (GWA) using a simple “filtration-oven drying” method under atmospheric pressure. The GWA was further annealed to obtain carbonized graphene-coated waste paper aerogel (C-GWA) for low density and excellent resilience. The C-GWA shows 3D porous structure formed by interpenetrated fibers and low density (25 mg/cm3). The pressure sensor based on C-GWA exhibits wide detection working range (0–132 kPa), ultra-low detection limit (2.5 Pa), and high sensitivity of (31.6 kPa−1). In addition, the pressure sensor can be used to detect human motions including the pulse of the human body, cheek blowing, and bending of human joints. The result indicates that the C-GWA-based sensor shows great potential for wearable electronic products.