Nanotech 2010 Vol. 1
Nanotech 2010 Vol. 1
Nanotechnology 2010: Advanced Materials, CNTs, Particles, Films and Composites

Nanoparticle Synthesis & Applications Chapter 3

Precipitant molar concentration effect on the upconversion emission in BaZrO3:Er,Yb nanocrystalline phosphor

Authors: L.A. Diaz-Torres, P. Salas, V.M. Castaño, J. Oliva, C. Angeles-Chavez

Affilation: Centro de Física Aplicada y Tecnología Avanzada, Universidad Nacional Autónoma de México, Mexico

Pages: 379 - 382

Keywords: upconversion, nanocrystals, Erbium, Ytterbium, hydrothermal method

Abstract:
Strong Blue, green, and red upconversion emission of Er3+ in sub-microcrystalline BaZrO3:(Yb3+Er3+) is observed. Powder samples were obtained by a facile hydrothermal process at 100ºC with different water to ethanol solvent ratios. The as synthesized nanocrystallites present a stable cubic perovskite phase only for a solvent ratio of 1:1, such behavior is preserved under subsequent annealing treatment up to 1000ºC. A slight phase segregation of rare earth oxides is observed for solvet ratios different of 1:1. Under IR excitation in the range between 900 and 1050nm the Er3+ blue emission was almost not present in single Er3+ doped BaZrO3, whereas it became easily observable when Yb3+ was added as codopant. Besides, both green and red upconversion emission of Er3+ are enhanced by around three orders of magnitude in comparison with the single Er3+ doped BaZrO3. The strong blue emission presents dependence on excitation power, and excitation wavelength, and solvent ratio. A possible mechanism for the upconversion process that leads to the observed blue, green and red emissions under NIR excitation is suggested based on the experimental results.

Precipitant molar concentration effect on the upconversion emission in BaZrO3:Er,Yb nanocrystalline phosphor

ISBN: 978-1-4398-3401-5
Pages: 976
Hardcopy: $189.95