Polypyrrole (PPy) attached on porous conductive sponge derived from carbonized graphene oxide coated polyurethane (PU) and its application in pressure sensor

A porous conductive sponge derived from carbonized graphene oxide (GO) coated polyurethane (PU) is made and polypyrrole (PPy) attached on the walls then. The as-obtained PPy/rGO@carbonized PU nanocomposite reserves the three-dimensional porous morphology of original PU sponge with PPy that the forms are nano spheres attached on the skeleton walls. After graphene oxide reduced to graphene, the conductivity and mechanical strength of carbonized PU increased. The as-made PPy/rGO@carbonized PU nanocomposite with good mechanical property was used as pressure sensor. Due to introduce PPy in the rGO@carbonized PU that could provide more contact sites which facilitating electron transfer and suffer more spatial deformation, the gauge factor (GF) of PPy/rGO@carbonized PU is 0.171 in compression strain range below 33.8% and 0.770 at larger compression strain region. Furthermore, the value of the other sensitivity of PPy/rGO@carbonized PU based pressure sensor S is 0.635 kPa 1. With the excellent performances, PPy/rGO@carbonized PU shows potential applications in pressure sensors under the deformations of compression.