Structural and magnetic behavior of Mn-doped SnO2 nanorods for diluted magnetic semiconductors

Abstract

The electrical and magnetic properties of low-dimensional materials like nanorods with defect-free lattice structures are remarkable; yet, structural defects, whether introduced purposefully or inadvertently, significantly modify the magnetic property. Thus, the existence of various cation or anion vacancies and interstitials in SnO₂ may alter their magnetic properties. In this study, Sn_1 − xMn_xO₂ nanoparticles (x = 0.00, 0.02, 0.04, and 0.06) were synthesised using chemical co-precipitation. The XRD pattern shows that manganese (Mn) ions were successfully incorporated into the tetragonal rutile crystal structure of tin oxide (SnO₂). The 445 cm^− 1 band in FTIR spectra indicates Sn–O bond stretching vibrations. The SEM image of SnO₂ shows that Mn inclusion forms nanorods. Sn, Mn, and O in EDX demonstrate the synthesized material’s purity. Photoluminescence peaks about 405 and 421 nm are caused by oxygen vacancies and tin interstitials. An X-ray photoemission spectroscopic analysis indicates a predominance of Sn⁴⁺ with a slight presence of Sn²⁺ valence states, attributed to oxygen vacancies, which leads to the formation of Mn⁴⁺ and Mn²⁺ states in the synthesized material. Mn doped SnO₂ samples’ magnetization versus magnetic field (M–H) curves at ambient temperature showed that increasing Mn concentration from 2 to 6% effectively caused ferromagnetic behaviour owing to Mn ions’ dominant magnetic interaction. To get ferromagnetic characteristics in these materials, the Mn dopant concentration must be properly optimized. The ferromagnetic characteristics of pure and Mn-doped SnO₂ diluted magnetic semiconductors have also been widely studied.