Probing structural, optical and magnetic properties of Sm-doped ZnO nanomaterials via experimental and DFT approach: Enhanced photocatalytic degradation and antibacterial performance

We prepared the pristine and Sm3+-doped ZnO nanostructures using an eco-friendly ball milling technique and investigated the physical properties of nanostructures by experimental methods and density functional theory approach. The reduction in crystallite size and increment in structural defects was witnessed due to Sm-doping. Decrease in band gap (from 3.27 to 3.02 eV) and enhancement of magnetic properties were observed with the in-crease in dopant concentration. The photocatalytic degradation potential of the samples towards the pollutants methylene blue (dye) and ciprofloxacin (antibiotic) improved with Sm3+ doping. The best performance was witnessed for the sample doped with 4 mol% of Sm2O3, which degraded the 93% and 95% of methylene blue (50 ppm) and ciprofloxacin (25 ppm) in 150 min and 210 min, respectively. Antibacterial activity towards the Escherichia coli and Staphylococcus aureus bacteria was also enhanced with the increase of Sm-content. Thus, Sm-doped ZnO nano -structures show good potential for photocatalytic and antibacterial applications.