Photoluminescence properties of Eu3+-doped ZnS nanocrystals prepared in a water/methanol solution

Abstract

Monodispersed ZnS and ${\mathrm{Eu}}^{\text{3+}}$ -doped ZnS nanocrystals have been prepared through the co-precipitation reaction of inorganic precursors ${\mathrm{ZnCl}}_2,$ ${\mathrm{EuCl}}_3,$ and ${\mathrm{Na}}_2\mathrm{S}$ in a water/methanol binary solution. The mean particle sizes are about 3–5 nm. The structures of the as-prepared ZnS nanoparticles are cubic (zinc blende) as demonstrated by an x-ray powder diffraction. Photoluminescence studies showed a stable room temperature emission in the visible spectrum region for all the samples, with a broadening in the emission band and, in particular, a partially overlapped twin peak in the ${\mathrm{Eu}}^{\text{3+}}$ -doped ZnS nanocrystals. The experimental results also indicated that ${\mathrm{Eu}}^{\text{3+}}$ -doped ZnS nanocrystals, prepared by controlling synthetic conditions, were stable.