Fabrication and characterization of Ca2Fe2O5 nanofibers photocatalyst by sol-gel assisted electrospinning at low-temperature

Abstract Brownmillerite Ca 2 Fe 2 O 5 nanocrystals were traditionally synthesized at temperatures higher than 800 °C. In this study, continuous Ca 2 Fe 2 O 5 nanofibers have been successfully synthesized by a sol-gel assisted electrospinning method for the first time, followed by heat treatment at a relatively low temperature (500 °C) for 2 h in air. This synthetic method may be extended to prepare other ternary metal oxides at relatively low temperatures. The crystal structure, surface morphology and microstructure are investigated by thermogravimetry (TG), X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The TG curve indicates that 500 °C is the lowest calcination temperature for obtaining pure Ca 2 Fe 2 O 5 nanofibers. The XRD analysis shows that the nanofibers possess highly crystalline structure without any impurity phase. The SEM results reveal that the obtained Ca 2 Fe 2 O 5 nanofibers are 200 nm in diameter. The photocatalytic activity of Ca 2 Fe 2 O 5 nanofibers is investigated for the photo-degradation of Rhodamine B (Rh B) aqueous solution under visible light. The result shows that Ca 2 Fe 2 O 5 nanofibers exhibit excellent photocatalytic activity compared with Ca 2 Fe 2 O 5 nanoparticles synthesized at the identical conditions by a sol-gel route.