Interfacial engineering strategy to improve the piezoresistive performance of polymer nanocomposites via chemical bonding of carbon nanotubes on graphene

Polymer nanocomposites have been extensively employed in the preparation of piezoresistive sensor. The nonlinear characteristic of electrical response under the mechanical force was a big hurdle for the application of existing sensors for stress monitoring. Herein, we reported nanocomposites composed of carbon nanotubes (CNTs)/graphene hybrid aerogel as conductive network and interpenetrated polydimethylsiloxane as matrix. CNTs and graphene were chemically connected via in-situ growth of nanotubes on the sheet of graphene through chemical vapor deposition method, and the hybrid aerogel improved the interfacial interaction between conductive network and polymer matrix. The developed nanocomposites showed high sensitivity and outstanding linear dependence on the applied stress to the material. The mechanism of such excellent performance was revealed by in-situ observation on the deformation of nanocomposites with a micromechanical testing device.