Reddish emission of europium doped zinc oxide nanophosphor prepared through precipitation route using sodium borohydride

The main objective of this research work is to develop a desired reddish emission of europium (Eu)-doped zinc oxide (ZnO) nanophosphor, prepared through precipitation route using sodium borohydride (NaBH4), as a precipitating agent and also study its structure, powder morphology as well as photoluminescence characteristics, especially asymmetric ratio or colour purity. X-ray diffraction of the calcined (600 degrees C) Eu (3 mol%)-doped ZnO powders confirmed the presence of pure phase ZnO and also suggested that the europium ions are incorporated in the lattice sites of Zn ions due to the increase in lattice volume as well as peak (101) shifting towards the lower angle. FESEM and TEM analysis confirmed that the particles of Eu-doped ZnO are elongated or elliptical rod-like, having length in the range of 200 nm - 400 nm as well as polyhedral in shape. Photoluminescence behaviour indicate an intense broad transition of D-5(0) -> F-7(2) (compared to transition of D-5(0) -> F-7(1)) corresponds to red emission, when the sample was excited at 464 nm. The ratio of integrated maximum emission intensities between D-5(0) -> F-7(2) and D-5(0) -> F-7(1) transitions was found to be similar to 5.9. The value of asymmetric ratio or colour purity and the position of CIE coordinates suggested that the Eu-doped ZnO nanopowders may be used as red emitting phosphor material. (C) 2019 Elsevier B.V. All rights reserved.