preparation and application of ni-co ldh/zncu2o4 nanoparticles as a high- performance electrode material for supercapacitors

Abstract: supercapacitors (scs) as a type of prospective energy storage systems, have been aroused extensive attentions, due to their rapid charge/ discharge process, high power density, long cycling lifetime, wide operation voltage and low maintenance cost [1]. in this work, a nanoarray electrode composed of zncu2o4 nanoparticles and ni-co layered double hydroxide (ni-co ldh) nanoparticles supported on ni foam (nf) is successfully constructed by an in-situ growth route. the physicochemical characteristics of the material were investigated by various techniques such as energy dispersive x-ray analysis (xrd) ,field-emission scanning electron microscopy (fesem), and transmission electron microscopy (tem). the electrochemical performance of the prepared ni-co ldh/zncu2o4/nf electrode as binder-free electrode for supercapacitor was examined by cyclic voltammetry (cv), and galvanostatic charge-discharge analysis (gcd) in 2 mol l–1 koh electrolyte and compared with zncu2o4/nf electrode. the proposed sc illustrated a high gravimetric specific capacitance (3511.77 f g-1 at 1 a g-1 and a capacity of 1114.51 f g-1 at 10 a g-1, good cycle stability (99.84% capability retention after 5000 cycles, together with ~100% coulomb efficiency). this work demonstrates that ni-co ldh/zncu2o4 nanoparticles could be a promising electrode for high-performance energy storage devices. the increased pseudocapacitive behaviors are related to its unique core/shell structure which provides facilitated ion diffusion, rapid electron transport kinetics, and good strain accommodation that makes it a potential choice for electrochemical energy storage owing to the their considerable electrochemical properties [2].