Tunable Ordered Nanostructured. alpha-Fe2O3 Lithium Battery Anodes by Nanocasting Technique Using SBA-15 Hard Silica Templates
Résumé
Nanostructured alpha-Fe2O3 have been obtained through a nanocasting strategy using different SBA-15 mesoporous silicas as hard templates. In order to tune the micro/mesoporous structure of the resulting alpha-Fe2O3 nanostructures, SBA-15 silica templates with different textural features were prepared by varying the temperature at which their synthesis was carried out. X-Ray powder diffraction, transmission electron microscopy and N-2 physisorption at 77 K techniques were employed for the structural-morphological characterization of the synthesized materials. Cyclic voltammetry and galvanostatic discharge/charge cycling tests were carried out to assess the electrochemical behaviour of the nanostructured alpha-Fe2O3 as a promising anode material for Li-ion cells. This work demonstrated that the structural-morphological features change accordingly to the different templates used and a careful control of the texture/particle characteristics is likely a fundamental variable which noticeably affects the cycling behaviour of the samples.