Solid-state grinding/low-temperature calcining synthesis of carbon coated MnO2 nanorods and their electrochemical capacitive property

Abstract

Taking malic acid as the carbon source, carbon coated-manganese dioxide (MnO₂) nanorods (MnO₂@C NRs) were prepared using a solid-state grinding/low-temperature calcining synthesis method. The morphology, structure and electrochemical capacitive property of MnO₂@C NRs were characterized using transmission electron microscopy, scanning electron microscopy, X-ray diffraction, surface area and pore size analysis and electrochemical methods. The results demonstrated that the thickness of the carbon layer on the surface of the MnO₂ NRs is about 3 nm and the MnO₂@C NRs have an improved capacitive performance and excellent long-term cycling stability. This method provides an easy route of synthesis with energy savings, cost effectiveness, environmental friendliness and large-scale production ability in the synthesis of carbon coated metal oxide nanomaterials.