Mechanochemically prepared polyaniline and graphene-based nanocomposites as electrodes of supercapacitors

Conductive nanocomposites based on polyaniline and graphene (PAni/Gr) were prepared by cheap and efficient mechanochemical method. The uniform distribution of Gr nanoparticles in the polymer matrix and the ordering of the polymer chains due to the action of mechanical shear stresses, which were established by TEM, stipulated high specific capacitance about 920 F g−1 in − 0.2–1.0 V vs. Ag/AgCl potential range. PAni/Gr-based electrodes are able to provide the specific capacitance of ~ 750 F g−1 at 2 A g−1 in symmetric supercapacitors (SSC) and stably cycle at the operating voltage V = 0.65 V for 10,000 charge-discharge cycles with 96% capacitance retention, whereas the increasing of V leads to the loss of stability as a result of the cathode degradation. PAni/Gr-based SSC possessed improved self-discharge showed high rate capability, and the specific power of such SSC could reach ~ 10 kW kg−1 at the specific energy of ~ 18 W h kg−1.