Structural, optical and energy gap evaluation of Mn2+/Cr3+ dual doped ZnS

Zn0.97Mn0.03S and Zn0.95Mn0.03Cr0.02S nanostructures were synthesized using co-precipitation method. X-ray diffraction analysis confirmed the ZnS cubic phase with preferred orientation along (1 1 1) direction. The shrinkage in crystallite size from 36 A (Zn0.97Mn0.03S) to 26 A (Zn0.95Mn0.03Cr0.02S) and the influence of Cr as well as Mn substitution on the structure and optical nature were examined. The addition of Cr not only diminished the size and also generated more defect related luminescent centres. The elevation in band gap by Cr addition was explained by Burstein–Moss effect and reduced crystallite size. The tuning of transmittance, energy gap as well size of ZnS nanostructure by Mn/Cr doping promote these materials for modern-electronic applications.