Experimental study demonstrates enhanced capacitance and cycling stability in hierarchically structured nanocomposites, indicating strong potential for advanced supercapacitors.
Key Points
To synthesize a hierarchically structured CoNi-LDH@Co(OH)2@CNFs nanocomposite electrode to overcome the low conductivity and structural instability of cobalt/nickel hydroxides in supercapacitors.
Assembled cobalt hydroxide (Co(OH)2) nanosheets and cobalt–nickel-layered double hydroxide (CoNi-LDH) nanoflowers onto carbon nanofibers (CNFs) via a two-step solvothermal method.
Fabricated an asymmetric hybrid supercapacitor device combining the CoNi-LDH@Co(OH)2@CNFs positive electrode with an activated carbon (AC) negative electrode.
The CoNi-LDH@Co(OH)2@CNFs electrode achieved a specific capacitance of 1179.4 F g−1 at 1 A g−1 and retained 80.6% capacitance at 20 A g−1.
The hybrid supercapacitor delivered an energy density of 41.4 Wh kg−1 at a power density of 788.4 W kg−1.
The assembled device maintained 90.4% of its initial capacitance after 5000 continuous charge-discharge cycles.