Study on the optical properties of Zn1−xMgxS (0 ≤ x ≤ 0.55) quantum dots prepared by precipitation method

Zn1−xMgxS (0 ≤ x ≤ 0.55) quantum dots (QDs) were successfully synthesized by precipitation method. The crystal structures, microstructures, and optical properties of the Zn1−xMgxS QDs were investigated using X-ray diffraction, scanning electron microscopy, and ultraviolet-visible and photoluminescence (PL) spectroscopy. The Zn1−xMgxS QDs were found to have a cubic crystal structure and an average crystallite size of 6.40–7.96 nm. It has been shown that an increase in doping Mg2+ concentration in Zn1−xMgxS QDs led to a gradual widening of the band gap and a weakening in the PL intensity of the Zn1−xMgxS QDs.

► ZnS:Mg was synthesized by precipitation method.
► The band gap was widened with increasing Mg2+ content.
► The emission intensity was weakened with increasing Mg2+ content.