Porously nanostructured MnO/C composites directed from polydopamine as high-performance supercapacitor electrodes

In this work, hierarchically porous MnO/carbon (MnO/C) microsphere materials were fabricated by a facile two-step approach. The MnO precursors and the polymerization of dopamine were synthesized simultaneously by chemical solution method at room temperature. The dopamine plays a key role in the formation of MnO/C, which guides the growth of porous spherical structures and acts as a carbon source. The enhancement of electrochemical properties and electrical conductivity strongly depend on the porous structure of the composite electrodes. Benefiting from the unique structures, the optimized MnO/C electrode delivered a high specific capacitance of 378 F·g −1 at 0.1 A·g −1 and retained over 96.66% of its initial capacitance after 1000 cycles at 1 A·g −1 , suggesting that MnO/C hybrid material has promising potential for practical supercapacitors.