Carbon coated NixCoyMn1-x-yO/Mn3O4 with robust deficiencies grown on nanoporous alloy for enhanced Li-Ion storage

Abstract Synthesis of nanostructured transition metal oxides with enriched deficiencies is a promising approach to accommodate the stress from volume changes and maximize conversion reactions. Here, we propose a rational design of carbon coated NixCoyMn1-x-yO/Mn3O4 electrode with robust metal/oxygen vacancies distributing in mixed crystal structure by self-combusting a nanoporous alloy and subsequently carbon coating. With partial Mn and Co ions replacing of some Ni2+ in NiO-basic crystal lattices, the enriched oxygen/metal vacancies build local electric field and enable enhanced Li+ storage capability. Additionally, the carbon layer synergy with the residual core-alloy can enhance the electronic conductivity of oxides and accommodate the volume change efficiently. On these foundations, the carbon coated NPM@oxides electrode demonstrates excellent electrochemical performance, showing a high reversible capacity of 901 mA h g−1 at 0.1 A g−1, and yielding high capacities of 851 mA h g−1 at 1 A g−1 and 649 mA h g−1 at 3 A g−1 after 200 cycles, respectively. This novel approach with low energy consumption is first used to serve as a model for the modification of nanoporous alloys, thus paving a new way to develop nanoporous metal based energy conversion devices with high-energy-density.