Synthesis of Dy-doped calcium hexaferrite (CaDyxF12-xO19) nanoparticles and their ferroelectric, dielectric, magnetic and photocatalytic properties under solar light irradiation

Abstract

Calcium hexaferrite (CaDyxFe12-xO19) was synthesized using the microemulsion method, incorporating Dy as a dopant at varying levels (x = 0.00, 0.1, 0.15, 0.20, 0.25, and 0.30). The effects of Dy-doping on the structural, magnetic, ferroelectric, dielectric and photocatalytic properties of CFO (CaDyxFe12-xO19) was evaluated. X-ray diffractometer, scanning electron microscopy, Fourier transform infrared spectroscopy, and UV–vis spectroscopy were employed for the characterization of the prepared samples. A single-phase hexagonal structure with space group P63/mmc was verified by the XRD analysis and the crystallite size was in the 31.74 nm to 38.77 nm range. The ferroelectric properties were examined using a hysteresis loop (P-E), revealing that higher dopant concentrations led to decreased saturation polarization (Ps) and retentivity (Pr). Electrical studies, including I-V measurements, aligned with semiconductor behavior, as evidenced by Curie temperature and activation energy values. Magnetic assessments demonstrated increased saturation magnetization (0.028–0.049 emu/g) and remanence (0.0046–0.0144 emu/g) upon Dy-doping. Photocatalytic experiments exhibited promising crystal violet dye degradation under visible light irradiation, with highly doped catalyst showing 85 % degradation within 100 minutes, surpassing the 42 % degradation with pristine CaFe12O19. The synthesized nanoparticles demonstrated promising stability and reusability in recycling experiments. Investigation of scavenger effects highlighted the crucial role of reactive •OH in dye degradation, surpassing the contributions of e- or h+ species. The CaDyxFe12-xO19 holds significant potential for efficient photocatalytic application in the removal of dyes from effluents under visible light irradiation.