Hollow Fe2O3 nanotubes derived from metal-organic framework for enhanced lithium storage and dye adsorption

Hollow nanoparticles are of great interest in energy storage and environmental remediation due to their improved mass transfer ability and unique void space for confined pollutants. Herein, fabrication of highly efficient and recyclable hollow porous γ-Fe2O3 nanotubes is reported by direct thermolysis of MIL-88A (Fe) precursors. Metal-organic frameworks (MOFs) that served as the precursors of the hollow γ-Fe2O3 nanotubes were first synthesized by a facile hydrothermal method followed by a one-step annealing process. As a proof-of-concept application, the as-synthesized hollow porous γ-Fe2O3 nanotubes were used in the lithium-ion battery and dye adsorption, respectively. Taking advantage of the hollow porous structure, γ-Fe2O3 nanotubes exhibited excellent lithium-ion batteries performance (1559 mAh g−1 at 100 mA g−1) and corresponding long cycle life (1093 mAh g−1 after 240 cycles at 100 mA g−1). At the same time, maximum methyl orange (MO) uptake capacity for the as-prepared hollow γ-Fe2O3 was calculated to be as high as 63.17 mg g−1. Moreover, this adsorbent also showed good reusability through the application of an external magnetic field, further highlighting the porous structure superiority of these hollow nanotubes. This proposed strategy could be extended to synthesize various hollow metal oxide porous nanoparticles with controllable structure, enhanced energy storage capacity and better environmental remediation performances.