Preparation of silk-like reduced graphene oxide/polyaniline composites using oxidant template-guided technique for supercapacitor

Abstract

The large-scale utilization of supercapacitors (SCs) demands urgently for high-performance electrode materials. Herein, the silk-like reduced graphene oxide/polyaniline (rGO/PANI) composites have been prepared by oxidant template-guided technique, it is an effective method for obtaining rGO/PANI composites with respect morphologies of PANI grow on rGO nanosheets due to δ-MnO2 acts as oxidant as well as reactive template. Initially, rGO nanosheets were employed as a reducing agent and substrate for the growth of δ -MnO2; next, aniline monomers were adsorbed on the surface of δ -MnO2 within rGO/MnO2 composites, and PANI was uniformly grown on the rGO nanosheets; finally, three of rGO/PANI composites with different mass percentages of PANI (22, 34, and 68 %) were obtained due to the varying amounts of δ -MnO2 and designated as rGO/PANI-1, rGO/PANI-2, and rGO/PANI-3, respectively. The silk-like rGO/PANI-1 and rGO/PANI-2 not only outperform rGO/PANI-3 and PANI in rate performance but also cycling stability. Moreover, the silk-like rGO/PANI-1 electrode material has an extraordinarily high-rate capability, retaining 84 % (435 ∼ 364 F/g) of its initial capacitance when the current density is increased from 0.25 to 10 A/g, and 80 % of the initial capacitance is maintained after 1000 cycles at 10 A/g. As well, the assembled rGO/PANI-1 symmetric SC demonstrates high rate capability and long term cycling stability. Therefore, the silk-like rGO/PANI-1 material’s outstanding capacitive property make it a prospective candidate for high-performance SCs.