Enhanced exciton emission from ZnO nano-phosphor induced by Yb3+ ions

• Published in: Materials letters Vol. 119; pp. 71 - 74
• Main Authors: Kabongo, G.L., Mhlongo, G.H., Mothudi, B.M., Hillie, K.T., Swart, H.C., Dhlamini, M.S.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.03.2014
• Subjects: Exciton; Nanocrystals; Photoluminescence; Sol–gel synthesis; Ytterbium; ZnO; Exciton; ZnO; Nanocrystals; Ytterbium; Sol–gel synthesis; Photoluminescence
• ISSN: 0167-577X; 1873-4979
• DOI: 10.1016/j.matlet.2013.12.076

In this work, the sol–gel method was used to prepare Ytterbium (Yb3+) doped ZnO nano-phosphors with different concentrations of Yb3+ ions. Their structural, morphological, photoluminescence, electronic states and the chemical composition analysis were investigated in detail. Both pure and Yb3+ doped ZnO were found to have hexagonal wurtzite structure with the particle size in the range of 4–7nm in diameter. Addition of Yb3+ ions into the ZnO host lattice led to enhanced exciton emission from ZnO indicating energy transfer from Yb3+ ions to ZnO or a reduction of oxygen related defects. TEM image and EDS spectrum of Yb3+ doped ZnO, along with the comparison of the PL emission from un-doped and Yb3+ doped ZnO nanophosphors. [Display omitted] •ZnO nanoparticles doped with Yb3+ ions were prepared by sol–gel.•(101) ZnO diffraction peak shifted to lower diffraction angles due to Yb3+ ions.•Addition of Yb3+ ions enhanced the ZnO exciton emission peak.•ZnO defects emission peak was severely reduced in the presence of Yb3+ ions.•XPS analysis confirmed the presence of Zn2+ and Yb3+ oxidation states in ZnO.