Structural, optical, and magnetic characterization of Mn-doped SrSnO ₃ nano perovskites

A comprehensive investigation was conducted on the ferromagnetic, optical, and local structural properties of undoped and Mn-doped SrSnO₃nanomaterials synthesized via chemical precipitation method. The study systematically explores the influence of Mn dopant concentration and valence states on the generation of oxygen vacancies, elucidating their pivotal role in modulating the magnetic behavior. Structural characterization using x-ray diffraction and Raman spectroscopy confirms the preservation of the orthorhombic perovskite phase with no detectable impurity phases across all doping levels. Fourier-transform infrared spectroscopy reveals a prominent absorption peak near 651 cm^-1, attributable to metal-oxygen vibrational modes. Raman spectra exhibit characteristic active modes within the 100-700 cm^-1range. X-ray photoelectron spectroscopy analysis provides insights into the oxidation states of Mn ions and the concentration of oxygen vacancies. Optical absorption measurements demonstrate a progressive redshift in the band gap energy with increasing Mn content, indicating modifications in the electronic structure. Multicolor photoluminescence emission confirms the presence of defect states in the samples. Electron paramagnetic resonance spectroscopy substantiates the existence of unpaired electrons in Mn-doped specimens. Room temperature magnetization studies reveal ferromagnetic ordering in all samples, with magnetic strength varying as a function of Mn doping concentration. The observed magnetic behavior is interpreted in terms of the<i>F</i>-center exchange mechanism. The unique interplay of structural, optical, and magnetic properties positions Mn-doped SrSnO₃nanomaterials as promising candidates for applications in magneto-optic devices and spintronic technologies.