Tunable magnetoresistance of core-shell structured polyaniline nanocomposites with 0-, 1-, and 2-dimensional nanocarbons

Core-shell structured polyaniline (PANI) nanocomposites with tunable magnetoresistance (MR) were obtained through the facial surface-initiated polymerization method with assistance of zero-, one-, and two-dimensional nanocarbons (carbon black, carbon fiber, carbon tube, and graphene). The improved dielectric properties and typical semiconducting behavior were observed in the PANI nanocomposites. And the quasi 3D electron conduction mechanism was observed in all the samples through Mott variable range hopping model, indicating that dimension of the nanocarbons does not affect the charge transport mechanism. Meanwhile, positive MR was observed in all the samples, and the MR value can be controlled by nanocarbons. When nanocarbon loading is 10.0 wt%, MR of graphene/PANI, carbon fiber/PANI, carbon black/PANI, and carbon tube/PANI were 15.6%, 14.7%, 9.5%, and 1.5%, respectively. The positive MR phenomenon was analyzed by the wave functional shrinkage model. The magnetic field and nanocarbons’ effects on the localization length, density of state at the Fermi level, average hopping length, and hopping energy were systematically studied. This work provides the guideline for the fabrication of tunable magnetic sensor or information storage device. Graphical abstract: Tunable magnetoresistance was reported in the polyaniline nanocomposites with zero-, one-, and two-dimensional nanocarbons as fillers. [Figure not available: see fulltext.]