Three-dimensional unified electrode design using CuO embedded MnO2 Nano-dandelions@Ni(OH)2 nanoflakes as electrode material for high-performance supercapacitors

In this study, we report successive chemical bath deposition (CBD) method to prepare three-dimensional (3D) hierarchical porous Ni(OH)2 nanoflakes on CuO-doped MnO2 nano-dandelions named as MnO2/CuO@Ni(OH)2 nanorod-nanoflake clusters. The as-prepared hierarchical MnO2/CuO@Ni(OH)2 nanorod-nanoflake clusters were composed of radially grown nanorods with a length of about 1.0 μm and surrounded by the interconnected nanoflakes clusters with a diameter of about 17 nm. Electrochemical evaluations revealed that the as-prepared electrode delivers a high specific capacitance of 3800 mF cm−2 at 1.0 mA cm−2 and long cycle life. The superior electrochemical performances were attributed to ideal ion transfer channels derived from radially grown 1D nanorods, which in combination with battery-type behavior of Ni(OH)2 nanoflakes, afford synergistic and multipurpose effects. Especially, the existence of CuO inner layer in the hierarchical MnO2/CuO@Ni(OH)2 nanorod-nanoflake clusters can fill the Schottky barrier at the interface between MnO2 and Ni(OH)2. This work suggest a new design of metal oxide/hydroxides and indicates that the hierarchical MnO2/CuO@Ni(OH)2 nanorod-nanoflake clusters can be considered as potential electrode material in high-rate supercapacitors. [Display omitted] •A 3D hierarchical MnO2/CuO nanorods@Ni(OH)2 nanoflakes was developed.•MnO2 nano-dandelions composed of nanorods serve as “charge superhighways”.•Doping with CuO which improves the electrode material conductivity.•Ni(OH)2 nanoflakes which serve as “ion reservoir” at electrode surface.•Using MnO2/CuO nanorods@Ni(OH)2 nanoflakes clusters as advanced unified electrode.