Solid-state-grinding method to synthesize NiCoFe alloy/NiCoFe-OH nanosheets for asymmetric supercapacitor

Solid-state-grinding is a facile method to prepare electrode materials, which is more beneficial to large-scale production. Herein, 3D NiCoFe alloy framework covered with NiCoFe-OH nanosheets hybrid architecture is constructed via solid-state-grinding and subsequent glycerol solvothermal treatment. Highly conductive NiCoFe alloy core stimulates its fast and charged transport, and as a result, high-capacity NiCoFe-OH nanosheets with rich active sites could participate into rapid electrochemical phase variation with KOH electrolyte. Moreover, the abundance of existing interfaces between the NiCoFe and NiCoFe-OH structures produces more electrochemical activity and presents further improvement to the electrical conductivity, both of which greatly regulate the electrochemical performance of electrode materials. NiCoFe/NiCoFe-OH//active carbon (AC) asymmetric supercapacitor (ASC) was assembled, showing a specific capacitance of 106 F g(-1) at 1 A g(-1), 36% of capacitance retention at 10 A g(-1) and 37.4 Wh kg(-1) of energy density at 756.4 W kg(-1) of power density. The most noteworthy is its excellent cycling stability, 89.3% of capacitance retention after 20,000 cycles. The simple and large-scale preparation method, high energy and power densities, and long cycling stability make NiCoFe/NiCoFe-OH//AC ASC an ideal energy storage device for driving LED bulbs and electronics, etc., as well as being able to charge/discharge repeatedly. (C) 2020 Published by Elsevier B.V.

Automated summary

Solid-state-grinding is an effective method for preparing electrode materials, leading to the construction of 3D NiCoFe alloy framework covered with NiCoFe-OH nanosheets hybrid architecture. This electrode material exhibits high capacity, excellent cycling stability, and is suitable for energy storage devices like supercapacitors.