One-Dimensional Core-Shell Architecture Composed of Silver Nanowire@Hierarchical Nickel-Aluminum Layered Double Hydroxide Nanosheet as Advanced Electrode Materials for Pseudocapacitor

Abstract

A one-dimensional (ID) core-shell architecture composed of silver nanowire@hierarchical nickel-aluminum layered double hydroxide nanosheet (Ag NW@NiAl LDH), where hierarchical NiAl LDH nanosheets grafted vertically along the ID silver nanowire backbone, is synthesized as the electrode material for supercapacitors. This well-designed in core-shell architecture not only provides efficient contacts between electrolyte and active materials but also facilitates the transport of electrons and ions and buffers the volume change, leading to high specific capacitance, fast redox reaction kinetics, and excellent cycling stability. As a pseudocapacitor electrode, the architecture exhibits a specific capacitance as high as 1246.8 F g(-1) at 1 A g(-1) and 80.3% of the capacitance can be retained after 5000 cycles at 10 A g(-1) in 6 M KOH aqueous solution. Remarkably, Ag NW@NiAl LDH electrode demonstrates 3.3 times higher specific capacitance than that of pure NiAl LDH electrode at a current density of 1 A g(-1). The rational design of ID metallic core and hierarchical shell architecture may open up new strategies for fabricating promising electrode materials for electrochemical energy storage.