Vertically oriented Ni-MOF@Co(OH)2 flakes towards enhanced hybrid supercapacitior performance

J Colloid Interface Sci. 2021 Jul:593:214-221. doi: 10.1016/j.jcis.2021.02.096. Epub 2021 Mar 9.

Abstract

Two dimensional (2D) materials, with ideal interlayer spacing for ion intercalation/de-intercalation, are quite appealing for hybrid supercapacitors (HSCs) in the pursuit of harvesting promising electrochemical performance. Integrating different 2D materials together is one effective strategy to achieve such goals. However, preserving the ion diffusion channel and accelerating electron transfer should be considered during the compositing process. Herein, we propose a two-step strategy to efficiently composite cobalt hydroxide (Co(OH)2) and Ni-based MOF (Ni-MOF-24), in which a vertically oriented Ni-MOF@Co(OH)2 array on nickel foam is obtained. The maximum specific capacitance of 1448 Fg-1 (2 Ag-1) is delivered by Ni-MOF@Co(OH)2. Accordingly, a hybrid Ni-MOF@Co(OH)2//AC HSC is thereof assembled, which outputsa high specific power of 22,400 W kg-1 and a considerable specific energy of 45.7 Wh kg-1.

Keywords: 2D material; Conductivity; Orientation; Specific energy; Supercapacitor.