Studies on structural and optical properties of pure and transition metals (Ni, Fe and co-doped Ni-Fe) doped tin oxide (SnO2) nanoparticles for anti-microbial activity

In this present work, pure and transition metal ions (Ni, Fe and co-doped Ni-Fe) doped SnO2 nanoparticles (NPs) were synthesized using a simple chemical co-precipitation method. Transition metal ions (Ni, Fe and co-doped Ni-Fe) were doped in order to study the influence of structural and optical properties. The synthesized samples were analyzed by using powder X-ray diffraction, scanning electron microscopy, energy dispersive X-ray analysis, UV-Visible spectroscopy, FT-IR, and photoluminescence spectroscopic techniques. SnO2 crystallites were found to exhibit tetragonal rutile structure with space group P42/mnm (136) with average particle size in the range of 20-30nm. Alsoconfirmed that all thedoped metal ions wereincorporated to SnO2. The UV-Vis-NIR spectroscopy revealed a significant red shift in the absorbing band edge due to increase in the amount of Ni, Fe and co-doped Ni-Fe contents. The SEM image shows the morphology of pure and doped (Fe, Ni and Fe-Ni co-doped) SnO2 NPs withlarge spherical shapes. In FT-IR spectra, the strong peaks are attributed to the antisymmetric stretching modeof O-Sn-O. The PL spectrum exhibits a strong blue emission peak. The antimicrobial studies were investigated against standard bacterial strains and enhanced anti-bacterial activity in doped and co-doped sampleswas observed, which can be attributed to the ROS and the particles were in the nanoscale regime.