Electrospun ZnFe2O4 nanotubes and nanobelts: Morphology evolution, formation mechanism and Fenton-like photocatalytic activities

Porous ZnFe 2 O 4 nanotubes and nanobelts have been fabricated through an efficient and facile approach of electrospinning followed by two-step calcination in atmosphere. The influences of electrospinning parameters such as metallic salt content, PVP content, the ratio of ethanol to water, stirring time and applied voltage on the composite fibers have been fully investigated. When the calcination temperature was increased from 600 °C to 650 °C, the ZnFe 2 O 4 nanotubes evolved into well-crystalline nanobelts due to the faster gas diffusion , more active grain growth and atomic diffusion rate caused by the relative high temperature. The plausible formation mechanism of ZnFe 2 O 4 nanotubes and nanobelts was proposed and discussed in detail. The photocatalytic activities for the photo-degradation of Rhodamine B (RhB) over ZnFe 2 O 4 nanotubes and nanobelts were evaluated under the UV-light irradiation. The degradation efficiency of nanotubes and nanobelts both can reach 99.7% after 20 min UV irradiation in presence of H 2 O 2 because of synergistic effects of Fe 3+ and H 2 O 2 , respectively, indicating the excellent Fenton-like photocatalytic properties of ZnFe 2 O 4 nanotubes and nanobelts. Additionally, the Fenton-like photocatalytic mechanism was also discussed.