Ultrahigh Rate Capability and Lifespan MnCo<sub>2</sub>O<sub>4</sub>/Ni‐MOF Electrode for High Performance Battery‐Type Supercapacitor
Fan Yang, Hao Guo, Yuan Chen, Mengni Xu, Wenhu Yang, Wenhu Yang, Mingyue Wang, Meng Yang, Junye Zhang, Lei Sun, Tingting Zhang, Wu Yang, Wu Yang
Abstract
Abstract MnCo 2 O 4 is derived from a Co/Mn bimetallic metal‐organic framework (MOF). Then Ni‐MOF is directly grown on the surface of the obtained MnCo 2 O 4 to form a nano‐flower structure with small balls. A large surface area, abundant active sites of MnCo 2 O 4 and porosity of Ni‐MOF allow the prepared MnCo 2 O 4 /Ni‐MOF composite material to deliver an excellent electrochemical performance. At the same time, an appropriate thermal treatment temperature of the MnCo 2 O 4 precursor is also very important for controlling the morphology of the obtained MnCo 2 O 4 and electrochemical performances of the resulted composite material including electric conductivity, specific capacitance and rate performance. The prepared MnCo 2 O 4 ‐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 MnCo 2 O 4 /Ni‐MOF has a good application prospect in the market.