Binder-free of NiCo-layered double hydroxides on Ni-coated textile for wearable and flexible supercapacitors

Recently, the combination of nickel (Ni) and cobalt (Co) binary hydroxides have been regarded as a promising class of materials due to their excellent redox reversibility and relatively high capacity. In this work, we demonstrate Ni and Co layered double hydroxides (NiCo-LDHs) on Ni-coated textile for wearable supercapacitor (SC) applications. Ni-coated textile was used as flexible current collector and NiCo-LDH nanosheets were deposited on textile as a pseudocapacitive materials. The electrochemical performances of NiCo-LDHs have been evaluated and optimized by varying the mole ratio of Ni and Co via hydrothermal process. The NiCo-LDH electrodes with Ni:Co ratio of 3:7 has the maximum specific capacitance, which is attributed to the CoOOH by improving the conductivity and enlarged interlayer spacing with intercalation of NO3-. Moreover, solid-state NiCo-LDH SC exhibits a maximum volumetric energy density of 1.25 mWh cm(-3) at a power density of 47.4mW cm(-3).