Facile fabrication and electrochemical performance of flower-like Fe3O4@C@layered double hydroxide (LDH) composite
Abstract
A novel core–shell structured Fe3O4@C@Ni–Al LDH composite containing a carbon-coated Fe3O4 magnetic core and a layered double hydroxide (LDH) has been successfully prepared by a combination of the hydrothermal method and a facile in situ growth process. The Fe3O4@C@Ni–Al LDH microspheres were characterized by X-ray diffraction (XRD), scanning and transmission electron microscopy (SEM and TEM), high-resolution transmission electron microscopy (HRTEM), Fourier transformed infrared (FT-IR), X-ray photoelectron spectra (XPS), and N2 adsorption/desorption methods. Owing to the unique layered feature, the composite displays core–shell structure with flower-like morphology, ultra-high surface area (792 m2 g−1) and specific pore size distribution. Moreover, the as-synthesized Fe3O4@C@Ni–Al LDH microsphere as an electrode material was fabricated into a supercapacitor and characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge–discharge measurements. It turned out that the Fe3O4@C@Ni–Al LDH exhibits specific capacitance of 767.6 F g−1, good rate capability, and remarkable cycling stability (92% after 1000 cycling). Therefore, such a novel synthetic route to assemble the high-performance electrochemical capacitor may open a new strategy to prepare other materials with largely enhanced electrochemical properties, which can be of great promise in energy storage device applications.