A new asymmetric supercapacitor based on λ-MnO2 and activated carbon electrodes

A B S T R A C T Lithium-ion intercalated compound λ-MnO2 was used as positive electrode in asymmetric supercapacitor with activated carbon used as negative electrode in 1 mol L−1 Li2SO4 aqueous electrolyte solution. Phase composition, morphology and particle sizes of λ-MnO2 were studied by powder X-ray diffraction (XRD) and scanning electron microscopy (SEM). Electrochemical capacitive …