Room temperature ferromagnetism in ZnS and ZnO nanoparticles

Abstract

This article deals with the structural and optical properties of zinc oxide and zinc sulfide nanoparticles synthesized by chemical precipitation method. X-ray diffraction study confirmed the wurtzite structure of zinc oxide and the cubic structure of zinc sulfide. The average crystallite size, the lattice constant, and unit cell volume were calculated from the x-ray diffraction study. The ultraviolet-visible absorption spectra and the Tauc’s plot were confirmed the energy gap of zinc sulfide and zinc oxide samples to be 5.1 eV and 3.73 eV, respectively. Fourier Transformation Infrared spectra confirmed the formation of zinc oxide and zinc sulfide through the appearance of peaks between 618 cm⁻¹- 439 cm⁻¹. The photoluminescence spectra confirmed the violet emission from ZnO and UV from ZnS. The transmission electron microscope study also confirmed the existence of particles in nanometer size. Composition analysis confirmed the existence of zinc, sulfur, and oxygen. The vibrating sample magnetometer results depict that the zinc sulfide and zinc oxides are ferromagnetic at room temperature. Electron paramagnetic resonance spectra also confirmed the ferromagnetic nature of zinc sulfide and zinc oxide samples.

Keywords:

• ZnO Nanoparticles
• ZnS Nanoparticles
• crystal structure
• microstructure
• photoluminescence
• d0 ferromagnetism