High surface area V-doped Ni(OH)2 honeycomb nanostructures as excellent electrode material for supercapacitor applications

The morphology and specific performance could be enhanced by doping-induced material defects leading to crystal imperfections. In this case, the pseudocapacitive characteristics of a hydrothermally synthesized V-Ni(OH)2 honeycomb-like structure are improved. The SEM study demonstrated that V-doping modifies the shape of Ni(OH)2 nanoparticles into a honeycomb-like structure, increasing the electrochemically active surface area and drastically increasing the electrochemical performance as measured through CV, GCD and EIS. The V0.03Ni0.97(OH)2 sample revealed higher performance with a specific capacitance of 1646.52 F/g at a current density of 1 A/g owing to excellent electrical conductivity and better charge transportation. The V0.03Ni0.97(OH)2 also exhibits outstanding electrochemical stability, with retention rates of 86 % after 5000 GCD cycles. The power law (b = 0.805) exhibited a pseudocapacitive nature, which displays increasing behavior with scan rate and particularly achieves 78.53 % at 50 mV/s. Thus, the CV, GCD and EIS showed that the V0.03Ni0.97(OH)2 sample had a higher conductivity, better ion transport, and a large number of active redox sites, making it a potential candidate to be employed in energy crisis situations, i.e. supercapacitors.