Tuning effect of Sn doping on structural, morphological, optical, electrical and photocatalytic properties of iron oxide nanoparticles

The pure and tin-doped iron oxide nanoparticles were synthesized by using the microwave irradiation method by varying the different wt% of Sn. Samples with better quality were prepared using 0.1 mol of Hexadecyl trimethyl ammonium bromide (HTAB) as surfactant. The influence of Sn levels lead to change in morphology of rhombus shaped platelets at lower doping levels of Sn into spherical shaped particles at higher doping levels. The respective change due to the Sn wt% in iron oxide was also altered the particle size, which was verified with the help of XRD and HR-TEM studies. The diffusion of Sn in an iron oxide lattice by incorporating Fe3+ sites were confirmed with the help of XPS spectrum. The electrical conductivity change was observed due to Sn doping levels in iron oxide. The tuning of bandgap variations on electrical conductivity was confirmed due to decrease of conductivity of higher doping level of Sn in iron oxide nanoparticles. The bandgap of iron oxide nanoparticle was tuned from 2.21 eV to 2.44 eV due to the incorporation of Sn in an iron oxide lattice. The change in band gap energy due to this reason is highly influenced on degradation of methylene blue dye. Photocatalytic activity under sunlight is clearly identified by the degradation.