Synthetic melanin facilitates MnO supercapacitors with high specific capacitance and wide operation potential window

Although tremendous efforts have been devoted to manganous oxide (MnO)-based hybrid electrode materials, the rational design and facile preparation of high-performance MnO hybrid supercapacitors are still full of challenges, due to the inevitable agglomeration and limited stability of MnO within carbon matrixes. In this work, we developed a direct one-pot polymerization method to synthesize a series of Mn ion doped polylevodopa [P(L-DOPA)] synthetic melanin nanoparticles (Mn@SMNPs) for further transforming into small-sized hybrid carbon nanoparticles (MnO@CNPs, 20-80 nm) consisting of many stable Mn-related chemical bindings (C-N-Mn). The obtained MnO@CNPs electrode materials with physically spatial protection and well distribution of MnO could display high specific capacitance values (e.g., 545 F g(-1) at 0.5 A g(-1) in 6 M KOH electrolyte) within a wide operation voltage of 1.3 V. This work will continue to provide an inspiration towards the fabrication of the next-generation of high-performance synthetic melanin-based energy storage materials and devices.

Automated summary

In this study, high-performance MnO hybrid carbon nanoparticles were successfully synthesized using a direct one-pot polymerization method, displaying high specific capacitance values in 6 M KOH electrolyte. This work will contribute to the fabrication of the next-generation high-performance synthetic melanin-based energy storage materials and devices.