Bimetallic vanadium cobalt diselenide nanosheets with additional active sites for excellent asymmetric pseudocapacitive performance: Comparing the electrochemical performances with M-CoSe 2 (M = Zn, Mn, and Cu)
Journal
Journal of Materials Chemistry A
Journal Volume
7
Journal Issue
20
Pages
12565-12581
Date Issued
2019
Author(s)
Abstract
Recently, bimetallic selenides have been considered as efficient electrocatalysts towards various electrochemical applications. Here, we demonstrated the synthesis of different transition metals (M = V, Zn, Mn, and Cu) incorporated into CoSe2 (M-CoSe2). The pseudocapacitive behaviours of the M-CoSe2 were enhanced due to the introduction of multiple redox properties and greater intrinsic electronic conductivity. Among them, bimetallic V-CoSe2 deposited on nickel foam (V-CoSe2/NF) exhibited a substantial specific surface area, high specific capacitance (1830.2 F g-1 at 1.5 A g-1), long-term cycling stability (118% retention, 5000 cycles) and low internal charge transfer resistance (Rct = 36.74 Ω). Thus, an asymmetric device assembled from V-CoSe2 and activated carbon (AC) exhibited an excellent energy density of 103.03 W h kg-1 at a power density of 1200 W kg-1. In summary, this work presents a new strategy to develop defect-rich transition metal selenides for high energy density supercapacitor devices.
Type
journal article