Exploring the impact of calcination parameters on the crystal structure, morphology, and optical properties of electrospun Fe 2 TiO 5 nanofibers.

Nanostructured Fe 2 TiO 5 (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 Fe 2 TiO 5 with high crystallinity and a large specific surface area. Herein, Fe 2 TiO 5 nanofibers were synthesized via 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 Fe 2 TiO 5 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 ( S BET = 64.4 m 2 g -1 ). This work opens new opportunities in the synthesis of Fe 2 TiO 5 nanostructures using the electrospinning method and a subsequent optimized calcination process for energy-related applications.