Structure, morphology and properties of ZnS crystal irradiated by electrons of different fluences

Abstract

The effect of 2[Formula: see text]MeV energy electrons with fluences from [Formula: see text] to [Formula: see text] electron/cm2 on the crystal structure, surface morphology, absorption spectrum, band gap, Raman spectrum and microhardness of ZnS crystal was investigated. The crystal structure of ZnS is face-centered cubic with space group F-43m. Upon irradiation with a fluence of [Formula: see text] electron/cm2, the unit cell parameter decreased by 0.0195[Formula: see text]Å, and the coordinates of the Zn[Formula: see text] ions were changed. Irradiation with fluences ranging from [Formula: see text] to [Formula: see text] electron/cm2 increased crystallite size from 20[Formula: see text]nm to 28[Formula: see text]nm. The study of the surface morphology of the ZnS single-crystal revealed that irradiation caused a reduction in both the width ([Formula: see text]) and height ([Formula: see text]) of the surface roughness. The band gap of the ZnS single-crystal decreased from 3.521 to 3.506[Formula: see text]eV when irradiated with fluence electrons from [Formula: see text] to [Formula: see text][Formula: see text]electron/cm2. Raman spectrum observations showed an increase in the longitudinal optical (LO) mode peak (350[Formula: see text]cm[Formula: see text]) intensity following the irradiation of ZnS single-crystal with electrons. The microhardness of the ZnS single-crystal showed an exponential increase by 20% when irradiated with fluences from [Formula: see text] to [Formula: see text][Formula: see text]electron/cm2.