Ce–Nd codoping effect on the structural and optical properties of TiO2 nanoparticles

Abstract

Abstract We report the changes in the structural and optical property of TiO 2 nanoparticles on codoping Ce–Nd ions. X-ray diffraction clearly demonstrates the structural changes occurring in the codoped TiO 2 nanoparticle. Oxygen defects disturb the Ti O bonds in the TiO 6 octahedra and result in the shifting and broadening of the Raman E g peak. Pure TiO 2 nanoparticles show absorption peak in the UV region. However, codoped TiO 2 nanoparticles exhibit absorption peaks in the visible region corresponding to the f–d and f–f electronic transition of Ce 3+ and Nd 3+ in the crystalline environment of TiO 2 . The visible emission peaks of pure and codoped TiO 2 nanoparticles are mainly associated with oxygen vacancies. Incorporation of cerium intensifies the visible emission peaks of TiO 2 nanoparticles. On the other hand, codoping of Nd forms some non radiative recombination centres and increases the possibility of emission energy transfer among dopants, defects, thereby quenching the intensity of the visible emission peaks.