Exploring the impact of calcination parameters on the crystal structure, morphology, and optical properties of electrospun Fe₂TiO₅ nanofibers

Abstract

Nanostructured Fe₂TiO₅ (pseudobrookite), a mixed metal oxide material holds significant promise for utilization in energy and environmental applications. However, its full application is still hindered due to the difficulty to synthesize monophasic Fe₂TiO₅ with high crystallinity and a large specific surface area. Herein, Fe₂TiO₅ nanofibers were synthesized <i>via</i> a versatile and low-cost electrospinning method, followed by a calcination process at different temperatures. We found a significant effect of the calcination process and its duration on the crystalline phase in the form of either pseudobrookite or pseudobrookite-hematite-rutile and the morphology of calcined nanofibers. The crystallite size increased whereas the specific surface area decreased with an increase in calcination temperature. At higher temperatures, the growth of Fe₂TiO₅ nanoparticles and simultaneous coalescence of small particles was noted. The highest specific surface area was obtained for the sample calcined at 500 °C for 6 h (<i>S</i> _BET = 64.4 m² g^-1). This work opens new opportunities in the synthesis of Fe₂TiO₅ nanostructures using the electrospinning method and a subsequent optimized calcination process for energy-related applications.