Trapping of Ce electrons in band gap and room temperature ferromagnetism of Ce4+ doped ZnO nanowires

Abstract

Rare-earth (RE) metal doped ZnO nanowires have been fabricated through a simple, quick, and versatile low temperature soft chemical method. The average length and diameter of nanowires lie in range of 5μm and 60nm, respectively. Raman and x-ray photoelectron spectroscopy studies demonstrate that Ce has 4+ oxidation state and successfully substitutes Zn up to 2.5% into ZnO single phase wurtzite structure. Doping of Ce shows a remarkably prominent large redshift of 22nm in the UV region of the band gap, with an increase in the intensity of green emission band due to charge transfer of Ce4+ dopant. In addition, it has been interestingly found that RE (Ce) doped ZnO nanowires exhibit room temperature ferromagnetism, which makes them potential for spintronic devices with excellent optical characteristics.