Morphology-Controlled Synthesis and Electrochemical Characteristics of Fe2O3 Nanorods

In this work, highly uniform single crystal Fe2O3 nanorods have been synthesized by a facile hydrothermal method in the presence of dihydrogen phosphate ions. Phosphate ions were speculated capping to the sidewalls of Fe2O3 nanocrystals, and resulted in the anisotropic growth of hematite crystals along their [006] zone axis. Fe2O3 nanorods with various aspect ratios have been realized by applying different phosphate concentration of 0.1-0.4 mM. The electrochemical properties of Fe2O3 nanorods showed that the samples with the smallest aspect ratio possessed superior specific capacitance and stability. It was speculated that the larger specific area of the Fe2O3 nanorods with the shortest axial length facilitated the efficient access of electrolyte ions to the electrode surface, and thus would aid in delivering the high pseudocapacitance. These results provide a promising route to obtain the desired hematite-based energy storage materials.