Highly ordered iron oxide nanotube arrays as electrodes for electrochemical energy storage

Highly ordered α-Fe2O3 nanotube arrays have been fabricated by a simple and cost-effective anodization method on iron foils. The α-Fe2O3 nanotube arrays exhibit high specific capacitance (138 F·g− 1 at 1.3 A·g− 1), remarkable rate capability (91 F·g− 1 at 12.8 A·g− 1) and good cycling stability (the capacitance retention close to 89% after 500 cycles), due to the unique nanostructures of the α-Fe2O3 nanotube arrays, which providing high surface area, fast ion transport pathways and robust structures. These features made the α-Fe2O3 nanotube array electrode very attractive for supercapacitor applications.

► Highly ordered iron oxide nanotube array prepared by anodization was first applied as the electrode for supercapacitor.
► The 1-D nanostructure of the anodized α-Fe2O3 nanotubes ensures good electrochemical performance of the electrode, which is attractive for supercapacitors.
► The anodic α-Fe2O3 provides a robust structure with high surface area and fast ion transportation.