Metal-Node-Engineered MOF-Derived Cobalt Manganese Selenide with Synergetic Surface Tailoring for Energy Storage Applications

Nickel foam-supported binder-free cobalt manganese selenide (CoMnSe@NF) was grown by in situ deposition using metal organic frameworks (MOFs) as the template with metal node engineering. The CoMnSe@NF electrode employed as the positive electrode for supercapacitors delivered well-pronounced conductivity, a high areal capacity (C_a) of 1714 mC cm^-2 at 1 mA cm^-2, and a specific capacity (C_s) of 519 C g^1- (1 A g^-1) withstanding over 5000 cycles with a good retention of 87% of its initial capacity. The outstanding electrochemical profile of CoMnSe@NF can be credited to the tailor-made synergetic surface, bearing densely packed 2-dimensional sheets harboring numerous redox sites with an even distribution of voids, allowing easy passageway and diffusion of the electrolyte. Armed with the said caliber of CoMnSe@NF, the asymmetric device fabricated (CoMnSe@NF-2h//O, N, S@AC@NF) delivered a remarkable specific capacity (C_s) of 139 C g^-1, maximum energy density (E_s) of 35.47 W h kg^-1, and a power density of 11,500 W kg^-1, remaining intact beyond 10,000 charge-discharge cycles and retaining 82.6% of the initial capacity.