TiO2nanotube arrays grafted with Fe2O3 hollow nanorods as integrated electrodes for lithium-ion batteries

Abstract

Novel nano-heterostructures composed of Fe₂O₃ hollow nanorods on both the outer and inner surface of the aligned TiO₂ nanotube arrays (TNAs) have been fabricated by growing FeOOH nanospindles onto the TNAs, and then followed by thermal transformation in air. Owing to their structural advantages, such a hierarchical architecture exhibits superior electrochemical performance with a remarkable areal capacity of over 600 μA h cm⁻² at a current density of 100 μA cm⁻² for 50 cycles (∼680 μA h cm⁻² at 100 μA cm⁻²). This hierarchal structure might be easily integrated as a binder-free electrode for microscale lithium-ion batteries considering the improved performance and the simple synthesis.