In situ growth of ordered polyaniline nanowires on surfactant stabilized exfoliated graphene as high-performance supercapacitor electrodes

Combining conducting polyaniline (PANI) nanowires with surfactant (tetrabutylammonium hydroxide) stabilized microwave-exfoliated graphene (TMEG) sheets leads to hierarchical nanostructure PANI/TMEG composites. PANI nanowires array are aligned vertically on TMEG substrate via in situ polymerization. TMEG, a support material, provide more active sites for nucleation of PANI and improve mechanical strength the electrode, and thus reducing the swelling/shrinking during the doping/dedoping. The PANI/TMEG composite electrode containing 10% TMEG exhibits an excellent specific capacitance as high as 1255 F g−1 at 1 A g−1, which is much higher than pure PANI (626 F g−1) and TMEG (115 F g−1). Moreover, the composite electrode exhibits 90% capacitance retention after 2000 cycles. The remarkable electrochemical performance is attributed to the hierarchical nanostructure electrode, which leads to reducing the diffusion length, facilitating the ionic motion and enhancing the rate performance of the electrode. The attractive characteristics showed in these TMEG supercapacitors make them potential candidates for future energy storage systems.