Ultrahigh Rate Capability and Lifespan MnCo₂O₄/Ni‐MOF Electrode for High Performance Battery‐Type Supercapacitor

Abstract

MnCo2O4 is derived from a Co/Mn bimetallic metal‐organic framework (MOF). Then Ni‐MOF is directly grown on the surface of the obtained MnCo2O4 to form a nano‐flower structure with small balls. A large surface area, abundant active sites of MnCo2O4 and porosity of Ni‐MOF allow the prepared MnCo2O4/Ni‐MOF composite material to deliver an excellent electrochemical performance. At the same time, an appropriate thermal treatment temperature of the MnCo2O4 precursor is also very important for controlling the morphology of the obtained MnCo2O4 and electrochemical performances of the resulted composite material including electric conductivity, specific capacitance and rate performance. The prepared MnCo2O4‐600/Ni‐MOF shows an ultrahigh rate performance (when the current density increases from 1 to 10 A g−1, the capacitance retention rate is as high as 93.41 %) and good cycle stability (the assembled asymmetric supercapacitor advice delivers a capacitance retention rate of 94.74 % after 20 000 charge and discharge cycles) as well as a relatively high specific capacitance. These excellent electrochemical properties indicate that MnCo2O4/Ni‐MOF has a good application prospect in the market.

Potential Applications of Nickel‐Based Metal‐Organic Frameworks and their Derivatives

“…Various NiÀ MOF based composites have been prepared, which demonstrated efficient EMs for high-performance SCs. Yang et al [148] reported MnCo 2 O 4 /NiÀ MOF electrode with ultrahigh rate capability and lifespan for the highperformance hybrid SC that showed a high capacitance retention rate of ~95 % after 20 K GCD cycles. Zhang et al [149] reported Co 3 O 4 -NiÀ MOF/MWCNTs electrodes for a hybrid SC with better electrochemical performance (at 1.0 A/ g, with a Cs of 72.12 F/g) and higher cyclic stability (after 1k GCD cycles, ~80 % capacitance retention).…”

“…Various Ni−MOF based composites have been prepared, which demonstrated efficient EMs for high‐performance SCs. Yang et al [148] . reported MnCo 2 O 4 /Ni−MOF electrode with ultrahigh rate capability and lifespan for the high‐performance hybrid SC that showed a high capacitance retention rate of ∼95 % after 20 K GCD cycles.…”