Fabrication and magnetic properties of electrospun copper ferrite (CuFe2O4) nanofibers

Tetragonal copper ferrite (CuFe2O4) nanofibers were fabricated by electrospinning method using a solution that contained poly(vinyl pyrrolidone) (PVP) and Cu and Fe nitrates as alternative metal sources. The as-spun and calcined CuFe2O4/PVP composite samples were characterized by TG-DTA, X-ray diffraction, FT-IR, and SEM, respectively. After calcination of the as-spun CuFe2O4/PVP composite nanofibers (fiber size of 89 ± 12 nm in diameter) at 500 °C in air for 2 h, CuFe2O4 nanofibers of 66 ± 13 nm in diameter having well-developed tetragonal structure were successfully obtained. The crystal structure and morphology of the nanofibers were influenced by the calcination temperature. After calcination at 600 and 700 °C, the nature of nanofibers changed which was possibly due to the reorganization of the CuFe2O4 structure at high temperature, and a fiber structure of packed particles or crystallites was prominent. Crystallite size of the nanoparticles contained in nanofibers increases from 7.9 to 23.98 nm with increasing calcination temperature between 500 and 700 °C. Room temperature magnetization results showed a ferromagnetic behavior of the calcined CuFe2O4 samples, having their specific saturation magnetization (Ms) values of 17.73, 20.52, and 23.98 emu/g for the samples calcined at 500, 600, and 700 °C, respectively.

SEM images of electrospun CuFe2O4 samples calcined in air for 2 h at 500 °C (left) and 700 °C (right). The nanofibers calcined at 500 °C remained as continuous structures, and their diameters are 66 ± 13 nm, whereas after calcination at 700 °C, the nature of nanofibers changed, and a structure of packed particles or crystallites was prominent, which may be due to the reorganization of the CuFe2O4 structure at high temperature.Figure optionsDownload as PowerPoint slide