Potentiodynamic deposition of composition influenced Co1−xNix LDHs thin film electrode for redox supercapacitors

Current paper comprises the electrodeposition of nanostructured porous Co1−xNix layered double hydroxide (Co1−xNix LDHs) thin films on to stainless steel substrate by a potentiodynamic mode. The compositional impacts on the various properties of Co1−xNix LDHs are examined via structural, morphological, surface wettability and electrochemical studies. The nanocrystalline Co1−xNix LDHs thin films possess varying porous, nanoflake like morphology and superhydrophilic behavior by the composition influence. Electrochemical studies demonstrate the supercapacitive performance of Co1−xNix LDHs thin film electrodes. The maximal specific capacitance for Co1−xNix LDHs electrode is found to be ∼1213 F g−1 for composition Co0.66Ni0.34 LDH in 2 M KOH electrolyte at 5 mV s−1 scan rate owing specific energy of 104 Whkg−1, specific power of 1.44 kW kg−1 with ∼94% of coulomb efficiency and stability of electrode retained to 77% after 10,000th cycle. The high capacitance retention proposes the deposited Co1−xNix LDHs thin film as promising contender for supercapacitor applications.

► Co1−xNix layered double hydroxides by potentiodynamical mode.
► The Co1−xNix LDHs thin film electrodes as redox supercapacitor with specific capacitance ∼ 1213 F g−1.
► Highly electrochemical cyclic stability retained 77% after 10,000th cycle.
►  Co0.66Ni0.34 LDHs showed specific energy = 104 W h kg−1, specific power = 1.44 kW kg−1 and coulomb efficiency ∼94%.