Optical and magnetic studies of electrospun Mn-doped SnO2 hollow nanofiber dilute magnetic semiconductor

The hollow nanofibers of Mn-doped SnO2 were fabricated by electrospinning method. The structural and magnetic properties of the electrospun fibers calcined at 600 degrees C were studied. X-ray diffraction patterns of the nanofibers showed broad diffraction peaks and were indexed to the characteristic diffraction pattern of tetragonal SnO2. The hollow fiber micro-structure of Mn-doped and pure SnO2 were confirmed from the observed HRSEM and TEM analysis. Typical diameter of the hollow nanofibers was found to be around 150 nm. Strong emission peak in the visible region of the PL spectra characteristic of the optical activity of the SnO2 is obtained. Surface composition of the nanofiber and successful incorporation of Mn into SnO2 were confirmed from intense peaks recorded in the XPS spectra. Finally, a reasonable ferromagnetic transition observed at 10 K in the Mn-doped SnO2, substantiates that the presence of undetectable Sn-Mn solid solution or the formation of Mn based oxide secondary phases. It concludes that the induced ferromagnetism is only due to the precipitated impurity phases and does not arise from any intrinsic pure SnO2 or the dopant.