Synthesis of mesoporous birnessite-MnO₂ composite as a cathode electrode for lithium battery

Mesoporous polythiophene birnessite (b)-MnO₂ has been synthesized by a modified interfacial method to develop cathode electrode materials for lithium batteries. The N₂ adsorption/desorption isotherm test of mesoporous polythiophene MnO₂ shows a type IV hysteresis loop, which is characteristic of a mesoporous structure. Mesoporous polythiophene MnO₂ has a high surface area of 226 m² g^-1 with a pore diameter of 5.2 nm The mesoporous polythiophene b-MnO₂ cathode electrode for Li-ion battery exhibited an initial discharge capacity of 305 mAh g^-1 at a current density of 10 mA g^-1, which is almost equal to its theoretical capacity. When applying a current of 300 mA g^-1, mesoporous polythiophene MnO₂ electrode shows the initial discharge capacity of 211 mAh g^-1, which is 69% of its theoretical capacity. Mesoporous polythiophene MnO₂ shows high capacity and good cycle stability even at high current densities due to its high surface area and fast Li-ion diffusion path.