Facile hydrothermal synthesis and electrochemical properties of hollow urchin-like α-FeOOH

Abstract

Hollow urchin-like α-FeOOH was successfully prepared without template or surfactant, employing a facile route incorporating hydrothermal treatment with ammonium iron (III) sulphate solution. α-FeOOH was characterised by X-ray diffraction, thermal gravimetric analysis, scanning electron microscopy, transmission electron microscopy (TEM), high-resolution TEM (HRTEM) and Fourier transform infrared spectroscopy. The Ostwald ripening process was believed to be the main driving force for the formation of hollow urchin-like architectures. Furthermore, the electrochemical properties of hollow urchin-like α-FeOOH were investigated by cyclic voltammetry (CV) and galvanostatic charge–discharge measurements. The CV results implied that the capacitance was mainly associated with the redox mechanism. The specific capacitance value was 88.5 F/g calculated from the discharge curve at the current density of 0.5 A·g. The hollow urchin-like α-FeOOH shows a good electrochemical performance.