Improved dielectric, conductivity and magnetic properties of erbium doped α-Fe2O3 nanoparticles

Abstract

This work demonstrates the synthesis of erbium (Er3+) ion doped ⍺-Fe2O3 nanoparticles through sol–gel method. The synthesized nanoparticles were thoroughly characterized by various analytical techniques such as XRD, FESEM and EDS, which confirmed that the prepared nanoparticles belong to hexagonal crystal structure with R-3c space group and are well crystalline and highly dense. The as synthesized nanoparticles were studied for dielectric, conductivity and magnetic properties. From dielectric studies, an increase in dielectric constant was observed with the increase in temperature and decrease in frequency. With Er3+ ion doping, a considerable increase in dielectric constant was observed for all doping concentrations. The temperature dependent dc conductivity follows Motts law thereby confirming variable range hopping mechanism in these systems. The room temperature magnetization was observed to increase significantly by incorporating Er3+ ions into ⍺-Fe2O3 lattice. In addition, an exciting result of this study was that the Er3+ ion doped ⍺-Fe2O3 nanoparticles saturate at low applied field of around 10 kOe compared to pure ⍺-Fe2O3 system which does not saturate up to the maximum applied field of 20 kOe. Attaining high saturation magnetization at low applied magnetic field in Er3+ ion doped ⍺-Fe2O3 system could provide a novel platform for medical applications.