Effect of SHI on dielectric and magnetic properties of metal oxide/PMMA nanocomposites

Magnetic nanoparticles embedded in polymer matrices have excellent potential for electromagnetic device applications like electromagnetic interference suppression, etc. The NiO nanoparticles were synthesized by simple method. These nanoparticles were dispersed in PMMA matrix and films were prepared by casting method with varying concentrations of nickel oxide nanoparticles. These films were irradiated with 50 MeV Li⁺³ ions at a fluence of 5 × 10¹² ions/cm². AC electrical properties of pristine and irradiated samples were studied in wide frequency range. Dependence of dielectric properties on frequency, ion beam fluence and filler concentration was studied. The results reveal the enhancement in dielectric properties after doping nanoparticles and also upon irradiation, which is also corroborated with field-cooled-zero-field-cooled (FC-ZFC) susceptibility measurement in which magnetization is increased upon irradiation. The Fourier transform infrared (FTIR) spectroscopy analysis revealed the change in the intensity of functional groups after irradiation. Average surface roughness observed to change with filler concentration and also with the irradiation fluence as obtained from AFM analysis.