Synergistic effects of Mg and F doping on the photocatalytic efficiency of ZnO nanoparticles towards MB and MG dye degradation

This study focuses the effect of Mg doping level (0–12 at.% in steps of 3 at.%) on the photocatalytic efficacy of ZnO:F:Mg nanopowder synthesised using a simple cost-effective chemical method. The structural, surface morphological, photoluminescence studies were carried out for all the samples. The photocatalytic dye degradation study under visible light against the two different dyes viz methylene blue (MB) and malachite green (MG) revealed that ZnO:F:Mg nanopowder doped with 12 at.% of Mg shows superior photocatalytic activity compared to other doped and undoped samples for both the dyes examined. The degradation efficiency of undoped ZnO is found to be 65 and 74% for MB and MG, respectively, whereas the F + Mg co-doped ZnO nanopowder (10 + 12 at.%) exhibits enhanced photocatalytic activity against both the dyes and the degradation efficiency values for MB and MG are 88 and 97%, respectively. The reasons for this enhancement are addressed appropriately with the evidences obtain from photoluminescence and X-ray diffraction studies.