Multiphase approach for calculation of tunneling conductivity of graphene-polymer nanocomposites to optimize breast cancer biosensors

A multiphase approach for the estimation of the electrical conductivity of graphene-based products from the properties of graphene, tunnels, and interphase is proposed. First, a simple model estimates the conductivity of interphase around the nanosheets, and subsequently, the conductivity of pseudoparticles containing graphene, tunnels, and interphase is estimated. Finally, a progressed model estimates the conductivity of the systems containing a polymer and pseudoparticles. The predictions of the multiphase technique were evaluated through comparison with experimented values and by parametric analyses. The predictions showed good agreement with the experimental values. Furthermore, the results of parametric studies supported the correctness of the multiphase technique. Thin and large graphene nanosheets can increase the conductivity to 0.14 S/m, and a high filler concentration and the presence of large tunnels could enhance the conductivity to 50 S/m. The maximum conductivity of 0.016 S/m is gained by an interphase depth of 10 nm and a filler conduction of 2.5 × 10⁵ S/m. The developed model can be used for optimizing breast cancer biosensors since the conductivity is the main factor for detection.