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

• Published in: Journal of alloys and compounds Vol. 792; pp. 1191 - 1199
• Main Authors: Singh, Rahul, King, Abhishek, Nayak, Bibhuti B.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 05.07.2019; Elsevier BV
• Subjects: Asymmetric ratio; Borohydrides; Colour purity; Emission; Europium; Lattice sites; Morphology; Nanophosphors; Phosphors; Photoluminescence; Purity; Red emission; Sodium borohydride; X-ray diffraction; Zinc oxide; Zinc oxides; Colour purity; Zinc oxide; Red emission; Sodium borohydride; Asymmetric ratio; Photoluminescence
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2019.04.113

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 °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 5D0→7F2 (compared to transition of 5D0→7F1) corresponds to red emission, when the sample was excited at 464 nm. The ratio of integrated maximum emission intensities between 5D0 → 7F2 and 5D0 → 7F1 transitions was found to be ∼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. [Display omitted] •Reddish emission of Eu-doped ZnO successfully prepared using NaBH4.•Elongated or elliptical rod-like morphology and polyhedral shape of Eu-doped ZnO.•Intense broad peak of 5D0→7F2 as comparted to 5D0→7F1, when excited at 464 nm.•Asymmetric ratio and colour purity was found to be ∼5.9 and ∼82.6%, respectively.•Position of CIE coordinates is nearer to the standard red chromaticity coordinates.