The effect of PVP coating on structural, optical, dielectric, and magnetic properties of an Fe2O3 nanostructure material for device engineering

Abstract

The impact of polyvinylpyrrolidone (PVP) coating compositions (2gm, 4gm, and 6gm) on the phase, magnetic, and dielectric characteristics of an Fe₂O₃ nanostructured material synthesized by the co-precipitation method are demonstrated in this experimental work. Structural analysis confirms the formation of hematite with a rhombohedral crystal structure and a rod-like morphology. According to spectroscopic techniques, the blue shift in absorption signifies the existence of vacancies and efficient PVP adherence to the nanostructure surfaces. Photoluminescence (PL) spectroscopy was employed to analyze the synthesized samples and identify the presence of different vacancies. Fourier transform infrared spectroscopy (FTIR) investigation has confirmed the stretching vibration mode of Fe–O. However, the thermogravimetric analysis (TGA) demonstrated the thermal stability of iron oxide. Dielectric measurements revealed strong frequency-dependent behaviors, with tangent loss and relative permittivity decreasing with increasing frequency. Additionally, different PVP coating compositions have a significant impact on magnetic properties, with coercivity decreasing and remanence increasing with high PVP concentration. Because of the diluting effect of the nonmagnetic polymer, the 2g PVP Fe₂O₃ sample with a thicker coating has various saturation magnetizations. These results showed that PVP content is a crucial factor in adjusting the magnetic and dielectric properties of a hematite nanostructure material.