Journal of Fluorescence

, Volume 17, Issue 4, pp 444–451

Comparative Investigation on Nanocrystal Structure and Luminescence Properties of Gadolinium Molybdates Codoped with Er3+/Yb3+

Original Paper

DOI: 10.1007/s10895-007-0191-3

Cite this article as:
Pan, Y.X., Zhang, Q.Y. & Jiang, Z.H. J Fluoresc (2007) 17: 444. doi:10.1007/s10895-007-0191-3

Abstract

This paper reports on the comparative investigation of nanocrystal structure and luminescence properties of Er3+/Yb3+-codoped gadolinium molybdate nanocrystals Gd2(MoO4)3 and Gd2MoO6 synthesized by the Pechini method with citric acid and ethylene glycol. Their crystallization, structure transformation, and morphologies have been investigated by X-ray diffraction, thermogravimetric/differential scanning calorimetry, and transmission electron microscopy. It is noticed that Er3+/Yb3+-codoped monoclinic Gd2(MoO4)3 nanocrystals have shown an intense upconversion through a sintering of the organic complex precursor at 600°C. Furthermore, it transforms to orthorhombic Gd2(MoO4)3 when the precursor is sintered at 900°C. In counterpart of monoclinic Gd2MoO6, however, the monoclinic structure remains unchanged when the precursor is sintered at a temperature ranging from 600°C to 900°C. Intense visible emissions of Er3+ attributed to the transitions of 2H11/2, 4S3/24I15/2 at 520 and 550 nm, and 4F9/24I15/2 at 650 nm have been observed upon an excitation with a UV source and a 980 nm laser diode, and the involved mechanisms have been explained. It is quite interesting to observe obvious differences both in the excitation and the upconversion emission spectra of Er3+/Yb3+-codoped Gd2(MoO4)3 respectively with monoclinic and orthorhombic structure. The quadratic dependence of fluorescence on excitation laser power has confirmed that two-photons contribute to upconversion of the green–red emissions.

Keywords

NanophosphorGadolinium molybdateUpconversion luminescence

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  1. 1.Key Lab of Specially Functional Materials of Ministry of Education and Institute of Optical communicationSouth China University of TechnologyGuangzhouPeople’s Republic of China
  2. 2.College of ChemistrySouth China University of TechnologyGuangzhouPeople’s Republic of China