Facile preparation and performance of mesoporous manganese oxide for supercapacitors utilizing neutral aqueous electrolytes

Abstract

A facile and green strategy based on a redox reaction between potassium permanganate and ascorbic acid was developed to synthesize mesoporous manganese oxide walnuts (MPMOW) for supercapacitors. The formation procedure was performed in a one-step fashion. The as-prepared samples were fully characterized to study the morphology, chemical composition and physical properties. An N₂ adsorption-desorption test indicated that the surface area of the materials is up to 128 m² g⁻¹. When used as electrode materials for supercapacitors, this mesoporous manganese oxide electrode materials possessed high capacitance and good cyclic stability even after 2000 cycles at a relatively high current density (833.33 mA g⁻¹) in three alkali metal sulfate neutral aqueous electrolytes (Li₂SO₄, Na₂SO₄ and K₂SO₄). Moreover, the charge storage mechanisms have been discussed in detail.