Enhancing Specific Capacitance and Cyclic Stability through Incorporation of MnO₂ into Bacterial Nanocellulose/PPy·CuCl₂ Flexible Electrodes

Abstract

This study reports the polymerization of polypyrrole (PPy) in bacterial nanocellulose (BNC) membranes impregnated with manganese oxide (MnO 2 ). Prior to polymerization, nanosized MnO 2 is synthesized in situ using H 2 SO 4 and KMnO 4 . PPy is then polymerized in situ in the MnO 2 impregnated BNC membranes via chemical oxidation using copper chloride dihydrate (CuCl 2 ·2H 2 O) as the oxidizing agent using two different concentrations of pyrrole (Py): 0.04 and 0.08 mol L −1 with a 1:4 molar ratio of Py/CuCl 2 ·2H 2 O. Assembled symmetric supercapacitor devices exhibit specific capacitances as high as 1073 mF cm −2 (259 F cm −3 ) and a capacitance retention of 99.5% after 1000 cycles, which show that the combination of BNC membranes with a conductive polymer and a metallic oxide can be promising as an electrode for energy storage devices.