Fabrication and characterization of flexible and high capacitance supercapacitors based on MnO2/CNT/papers

Flexible paper-based supercapacitors were fabricated using carbon nanotubes (CNTs) and manganese oxides (MnO2), and their electrochemical properties were characterized in a three-electrode system. CNTs were synthesized via water-assisted chemical vapor deposition (CVD) and dispersed in water using the surfactant sodium dodecylbenzenesulfonate (SDBS). The solution containing dispersed CNTs was simply coated on papers by drop-dry method. MnO2 was then electrochemically deposited on the CNT-coated papers. The MnO2/CNT/paper supercapacitors showed high specific capacitance of 540 F/g. Specific energy and specific power were 20 Wh/kg and 1.5 kW/kg, respectively, at current density of 5 A/g in 0.1 M sodium sulfate (Na2SO4) aqueous solution. Demonstrated high capacitance of the paper-based electrochemical capacitor makes it a promising candidate for flexible and low-cost energy storage device applications.