Magnetic and electrochemical properties of CuFe2O4 hollow fibers fabricated by simple electrospinning and direct annealing

Abstract

Copper ferrite (CuFe₂O₄) hollow fibers were fabricated by direct annealing of electrospun precursor fibers with appropriate heating rate. The crystal structure, morphology, magnetic properties and electrochemical properties of as-made CuFe₂O₄ hollow fibers were investigated by using X-ray diffraction, Fourier-transformed infrared spectra, scanning electron microscopy, transmission electron microscopy, vibrating sample magnetometer, and electrochemical workstation. The results show that the appropriate heating rate of 0.5 °C min⁻¹ can result in the formation of hollow tetragonal structural CuFe₂O₄ fibers. Hollow fibers after annealing at high temperatures still retain the one-dimensional texture and the walls of hollow fibers consist of many nanoparticles. Magnetization results indicate that the CuFe₂O₄ hollow fibers have a ferromagnetic behavior and their specific saturation magnetization value increases with an increase in the annealing temperature. Moreover, the electrochemical results suggest that the capacitance characteristic of the CuFe₂O₄ hollow fibers is a typical pseudocapacitive capacitance. The value of the specific capacitance gradually decreases with the increase in the discharge current density.