Photostability and electrical and magnetic properties of cobalt oxide nanoparticles through biological mechanism of endophytic fungus Aspergillus nidulans

The study elaborates magnetic and electrical properties of greenly synthesized cobalt oxide (Co3O4) nanoparticles through endophytic fungus Aspergillus nidulans isolated from medicinal plant Nothapodytes foetida, which examines the ability of the nanoparticles to be magnetized and electrified, being one of the yardsticks for energy application. On increasing the precursor concentration from 2 to 10 mM, there is a shift in paramagnetic to weak ferromagnetic behavior of nanoparticles with the increase in saturation magnetization (M-s) from 0.161 to 7.75 emu/g. Frequency dependence of dielectric constant is found to increase with an increase in frequency, and the aforementioned nanoparticles can be used as a dielectric up to 1,50,000 Hz as dissipation factor is lesser than one. Besides, photostability study has indicated that the particles are stable for at least 45 days. Through liquid chromatography-mass spectrometry (LC-MS) analysis, phytochelatins are identified to be involved in the biosynthesis of nanoparticles.