Structural, optical and photoluminescence properties of Eu3+ doped ZnO nanoparticles

Odireleng Martin Ntwaeaborwa; Sefako J Mofokeng; Vinod Kumar; Robin E Kroon

doi:10.1016/j.saa.2017.03.067

Structural, optical and photoluminescence properties of Eu³⁺ doped ZnO nanoparticles

Spectrochim Acta A Mol Biomol Spectrosc. 2017 Jul 5:182:42-49. doi: 10.1016/j.saa.2017.03.067. Epub 2017 Apr 1.

Authors

Odireleng Martin Ntwaeaborwa¹, Sefako J Mofokeng², Vinod Kumar³, Robin E Kroon⁴

Affiliations

¹ School of Physics, University of the Witwatersrand, Private Bag 3, Johannesburg ZA2050, South Africa. Electronic address: ntwaeab@gmail.com.
² Department of Physics, CSET, University of South Africa, Johannesburg ZA1710, South Africa.
³ Photovoltaic Laboratory, Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016, India.
⁴ Department of Physics, University of the Free State, Bloemfontein ZA9300, South Africa.

PMID: 28391073
DOI: 10.1016/j.saa.2017.03.067

Abstract

The structure, particle morphology and luminescent properties of europium (Eu³⁺) doped ZnO nanoparticles (NPs) prepared by co-precipitation method are discussed. When excited using a 325nm He-Cd laser, undoped ZnO NPs exhibited weakly the well-known ultraviolet excitonic recombination emission (at ~384nm) and strongly broad band visible emissions associated with defects (at ~600nm). In addition, the ZnO NPs exhibited green emission at ~600nm associated with defects when excited using a monochromatized xenon lamp. Upon Eu³⁺ doping line emissions attributed to ⁵D₀→⁷F_1,2,3,4 transitions of Eu³⁺ ions were observed when the materials were excited using a monochromatized xenon lamp. The exchange interaction mechanism is identified as the cause for concentration quenching of the luminescence of Eu³⁺ doped ZnO NPs in this study.

Keywords: Co-precipitation; Concentration quenching; Defects; Nanoparticles (NPs); ZnO.