Influence of magnesium incorporation on the structural, optical, and electronic properties of chemically synthesized ZnO thin films: experimental observations and ab initio analysis

In this study, zinc oxide (ZnO) thin films doped with varying amounts of magnesium (Mg) were fabricated through a sol– gel process combined with spin coating. The influence of Mg incorporation on the structural, electrical, and optical behaviors of ZnO layers was thoroughly examined. X-ray diffraction confirmed that all prepared coatings exhibit a wurtzite-type hexagonal lattice with strong preferential growth along the c-axis. Within the visible spectrum, the films demonstrated an average optical transmittance of approximately 77 %, while increasing Mg content induced a noticeable red shift in the absorption edge. Furthermore, the electronic characteristics of ZnO were investigated using UV–visible spectroscopy and optical microscopy. Complementary <i>ab initio</i> simulations determined a band gap of 3.2 eV, with calculated density of states in excellent agreement with the measured optical responses. These outcomes highlight the capability of <i>ab initio</i> methods to reliably describe the electronic properties of ZnO-based materials.