Nanowire architectured porous bimetallic transition metal oxides for high performance hybrid supercapacitor applications

Abstract

The electrochemical performance of the Faradaic battery-type binary metal oxide electrodes is dependent on the desirable architecture and the optimal cationic ratio. Herein, we report one-dimensional nanowire-like bimetallic spinel Ni x Co 3-x O 4 (NCO) electrode materials for high performance hybrid supercapacitor (HSC) applications. This unique nanowire architecture is beneficial for providing abundant exposed active sites onto the large accessible surface area, which results in facilitating ion transporting pathways. Remarkably, the optimal NCO electrode with the ratio of Ni/Co of 1 to 1 (NCO11) achieves the maximum specific capacitance of 1033 F g À1 at 1 A g À1 and the excellent rate capability of 74.55% at 30 A g À1 , far exceeding those of their single counterparts. Furthermore, the as-assembled HSCs integrating NCO11 and AC electrodes deliver large energy and power densities of 41.54 W h kg À1 and 44.95 kW kg À1 with excellent cyclic retention (96.12%).

Transition metal dichalcogenide nanostructured electrodes without calcination for aqueous asymmetric supercapacitors

“…The electrochemical analysis was carried out at the temperature of ~18°C; this temperature was favorable without evaporation of the electrolyte throughout the analysis. The mass balance between the optimized NMS/NS@CC‐210 and AC@CC electrodes for the AEC device was estimated using the following equation 42,43 : Here, C s + , m + , and ∆V + indicate the specific capacitance, mass, and potential window of the NMS/NS@CC‐210 (positive) electrodes, respectively. In the same way, the C s − , m − , and ∆V − are the specific capacitance, mass, and potential window of the AC@CC (negative) electrode, respectively.…”

“…The electrochemical analysis was carried out at the temperature of $18 C; this temperature was favorable without evaporation of the electrolyte throughout the analysis. The mass balance between the optimized NMS/NS@CC-210 and AC@CC electrodes for the AEC device was estimated using the following equation 42,43 :…”

The synthesis of Ni/Mn hexacyanoferrate microcubes and nanorods for high‐performance asymmetric supercapacitor in neutral electrolyte

“…The asymmetric supercapacitors have combined the advantages of both battery‐type electrodes and capacitive‐type electrodes. The enhanced performance of asymmetric supercapacitors is due to the combination of intercalation/deintercalation occurring at the battery‐type electrode and the electrostatic absorption/desorption occurring at the capacitive‐type electrode, which enlarges the operating voltage window and subsequently increases the energy density of the device 10 …”

“…The enhanced performance of asymmetric supercapacitors is due to the combination of intercalation/deintercalation occurring at the battery-type electrode and the electrostatic absorption/ desorption occurring at the capacitive-type electrode, which enlarges the operating voltage window and subsequently increases the energy density of the device. 10 Because of the rich valence states of transition metals (TM), the oxides, [4][5][6][9][10][11] sulfides, [12][13][14][15][16] hydroxides [17][18][19][20][21][22][23][24][25][26] of transition metals, and their numerous composites have been widely investigated as the supercapacitor electrode materials of faradic supercapacitor. Recently, the application of transition metal hexacyanoferrates (TM-HCFs) as the electroactive materials of supercapacitor has also been investigated by many researchers due to their excellent redox reversibility, high ionic conductivity, superior environmental benignancy, low cost, and insolubility upon oxidation/reduction.…”

“…Because of the rich valence states of transition metals (TM), the oxides, 4‐6,9‐11 sulfides, 12‐16 hydroxides 17‐26 of transition metals, and their numerous composites have been widely investigated as the supercapacitor electrode materials of faradic supercapacitor. Recently, the application of transition metal hexacyanoferrates (TM‐HCFs) as the electroactive materials of supercapacitor has also been investigated by many researchers due to their excellent redox reversibility, high ionic conductivity, superior environmental benignancy, low cost, and insolubility upon oxidation/reduction 27‐52 .…”