Activated carbon/MnO₂ composites as electrode for high performance supercapacitors

Activated carbon (AC) was synthesized with various weight ratios of manganese dioxide (MO) through a simple hydrothermal approach. The electrochemical performance of the synthesized activated carbon/MnO₂ composites was investigated. The effect of the activated carbon/MnO₂ (AM) ratio on the electrochemical properties of the activated carbon/MnO₂ composites and the pore structure was also examined. The results show that the specific capacitance of the activated carbon material has been improved after the addition of MO. The as-synthesized composite material exhibits specific capacitance of 60.3 F g⁻¹ at 1 A g⁻¹, as well as stable cycle performance and 99.6% capacitance retention over 5000 cycles.