Applied Surface Science, Vol.465, 929-936, 2019
Ultrathin NiFe-layered double hydroxide decorated NiCo2O4 arrays with enhanced performance for supercapacitors
Designing and synthesizing core/shell nanostructures materials as binder-free electrodes is an effective strategy to enhance the electrochemical performance of supercapacitors. In this work, the hierarchical NiCo2O4@NiFe-layered double hydroxide core/shell arrays are successfully constructed via a stepwise hydrothermally grow method and investigated for application in supercapacitors. With the assistance of the hierarchical core/shell structures and the synergetic effect between NiCo2O4 and NiFe-layered double hydroxide nanosheets, the hybrid electrode discloses significant melioration in property, including the improvement in number of the electro-chemically active sites and short transport path lengths for both electrons and ions. Thus, the core/shell electrode exhibits remarkable electrochemical performance, such as a high areal capacity (12.3 F cm(-2)) and good cycling stability (83.1% capacitance retention after 2000 cycles). Our trials testify that the hierarchical NiCo2O4@NiFe-layered double hydroxide core/shell nanowire arrays are advantageous for potential applications in energy storage devices.
Keywords:Layered double hydroxide;Core/shell architecture;Supercapacitors;Electrochemical energy-storage