Improving the ferroelectric and ferromagnetic properties of multiferroic composite materials for the decomposition of synthetic dyes

Abstract

A multiferroic composite of xNi_0.6Zn_0.4Fe₂O₄/(1-x) (0.5Ba(Zr_0.2Ti_0.8)O₃-0.5(Ba_0.7Ca_0.3)TiO₃) (denoted as NZFO/BZT-BCT) with an average particle size of 100 nm was prepared by high-energy mechanical milling combined with the thermal annealing methods. The X-ray diffraction pattern indicates the presence of both Ni_0.6Zn_0.4Fe₂O₄ (NZFO) and (0.5BaZr_0.2Ti_0.8O₃) - 0.5(Ba_0.7Ca_0.3TiO₃) (BZT-BCT) phases in the multiferroic composite. At room temperature, the multiferroic composite exhibits a remanent magnetisation (Mr) of approximately 0.6 emu/g and a saturation magnetisation (Ms) of about 29.2 emu/g. It is worth noting that this nanocomposite displayed exceptional photocatalytic activity in degrading Rhodamine B (RhB). After irradiation with UV radiation for 180 minutes, the degradation efficiency of RhB reached 99%. The kinetic reaction of the RhB degradation was also assessed, revealing that the apparent first-order rate constant of NZFO/BZTBCT is kp=0,019 min⁻¹. With benefits such as easy fabrication and simple recovery using an external magnetic field, the NZFO/BZT-BCT multiferroic composite could be a potential candidate for photocatalytic environmental treatment.