A study of nano-structured manganese dioxides and their composites as electrode materials for micro supercapacitors

This paper presents the design, synthesis and characterization of nano-structured manganese dioxides (MnO₂) and their composites as electrode materials for micro supercapacitors. An optimized composite containing nano-MnO₂ powder exhibits a specific capacitance as high as 160F/g in 0.2M K₂SO₄ aqueous solution, and is compatible with micro fabrication process. Then a micro supercapacitor with 3D interdigital structure using the composite material as electrodes is achieved by MEMS fabrication technology. The micro supercapacitor has well-performed capacitive behavior under various scanning rates and has a large specific capacitance of 30mF/cm², which indicates that the composite is a promising material for energy storage on chips.