Zirconia Based Nanomaterials for Oxygen Sensors – Generation, Characterisation and Optical Properties

Janusz D. Fidelus, Witold Lojkowski, Donats Millers,
Larisa Grigorjeva, Krishjanis Smits and Robert R. Piticescu

Abstract: Microwave driven hydrothermal synthesis and hydrothermal synthesis were used to
obtain ZrO2 nanopowders. Their production with varying phase composition, the characterisation
and selected optical properties concerning their potential use as luminescence oxygen sensors are
reported. It was found that the powders obtained by the microwave driven hydrothermal method
and annealed at 750 0C in air show experiment repeatability within an accuracy of 6 %.

Solid State Phenomena Vol. 128 (2007) pp. 141-150

© (2007) Trans Tech Publications, Switzerland

pdf-iconDownload pdf

The Luminescence Properties of ZnO:Al Nanopowders Obtained by Sol-gel, Plasma and Vaporization-condensation Methods

Larisa Grigorjeva, Donats Millers, Krishjanis Smits, Claude Monty, Jules Kouam and Lassad El Mir

Abstract: ZnO nanocrystals were synthesized and characterized by XRD and SEM methods. The
luminescence spectra and decay kinetics were studied under pulsed laser excitation (266 nm, 8 ns).
ZnO and ZnO:Al powders were prepared by sol-gel and plasma chemical synthesis. These powders
were used as a raw material for the SPVD (Solar Physical Vapour Deposition) process. In this way,
the vaporisation-condensation phenomenon (VC) led to the formation of ZnO whiskers and
nanopowders. The luminescence properties of the VC nanopowders were studied and compared to
those displayed by the raw material. The Al dopant, present in the raw powders as a solid solution
and ZnAl2O4 precipitates, was only present as Al ions in the nanopowders after the SPVD. The blue
luminescence intensity increased considerably after SPVD. The whiskers type microstructures
showed nonlinear blue luminescence dependent on the excitation pulse density.

Solid State Phenomena 2007 Continue reading “The Luminescence Properties of ZnO:Al Nanopowders Obtained by Sol-gel, Plasma and Vaporization-condensation Methods”