Facile fabrication of polyaniline@γ-MnOOH on a buckypaper ternary composite electrode for free-standing supercapacitors

Ternary composites as electrode materials have attracted extensive attention due to their excellent electrochemical performance in energy-storage technologies as compared to single or binary composites. Herein, we demonstrated a facile two-step method to construct a new hierarchical nanocomposite by combing buckypaper (BP) with γ-MnOOH nanorods and polyaniline. BP is used as a conductive substrate for the synthesis of free-standing hierarchical electrodes. The structural characterizations revealed the growth of a hierarchical porous structure of the ternary electrode. The synthesized polyaniline@γ-MnOOH–BP ternary composite electrode shows a maximum specific capacitance of 567.5 F g−1 at a current density of 0.5 A g−1 and a relatively high areal capacitance of 301.2 mF cm−2 at a current density of 0.27 mA cm−2. This intriguing result is ascribed to the good combination of BP, γ-MnOOH, and PANI. We believe that this ternary composite electrode has potential in portable, environmentally friendly, and wearable applications for next generation energy-storage devices.