Room temperature ferromagnetism in Mn doped TiO 2 thin films: Electronic structure and Raman investigations

In this work dc-magnetization, electronic structural, and Raman investigations of Ti 1−x Mn x O 2 (x=0.00, 0.05, 0.10, and 0.15) thin films deposited on fused-quartz substrate by a simple and cost effective spray pyrolysis technique have been reported. X-ray diffraction revealed the formation of pure anatase TiO 2 phase devoid of elemental Mn clusters in all the Mn incorporated TiO 2 films. It is established by x-ray photoelectron spectroscopic (XPS) measurements that Ti ions substituted by Mn ions in both divalent and trivalent states in the TiO 2 matrix. No peak corresponding to Mn +4 could be evidenced by XPS. The Raman study has further established the formation of TiO 2 in anatase structure in both pure TiO 2 and Mn-doped TiO 2 films. The Ti 1−x Mn x O 2 films with x ≥ 0.05 exhibit ferromagnetic ordering at room temperature which arises most likely due to formation of bound magnetic polarons.