Gas sensitive luminescence of ZnO coatings obtained by plazmaelectrolytic oxidation

L. Grigorjeva, D. Millers, K. Smits, A. Zolotarjovs

The ZnO coatings on Zn substrate were obtained using plasma electrolytic oxidation method. The XRDand SEM methods were used for structural and morphological characterization of obtained coatings. Theluminescence of ZnO coatings were studied and compared with luminescence characteristics of ZnO sin-gle crystal. It is shown that luminescence intensity in ZnO defect band depends on oxygen concentrationin ambient atmosphere. The effect is of interest for oxygen sensing based on ZnO coating luminescence

Sensors and Actuators A 234 (2015) 290–293

doi:10.1016/j.sna.2015.09.018

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Advanced nanocrystalline ZrO2 for optical oxygen sensors

Janusz D. Fidelus and Witold Łojkowski, Donats Millers, Krisjanis Smits and Larisa Grigorjeva

Abstract It was shown that ZrO2 nanopowders and
nanoceramics can be used as an optical oxygen sensor,
where the luminescence signal is proportional to the
partial oxygen pressure in gases. The nanopowders were
obtained in a hydrothermal microwave driven process
followed by annealing at 750oC. Nanoceramics were
obtained by sintering at pressures up to 6 GPa and at
250oC so that grain growth did not occur. Luminescence
of both materials depends linearly on the oxygen content
in nitrogen-oxygen mixtures for 2.1% – 25 vol% oxygen
content. For luminescence excitation using a laser beam,
the luminescence intensity decreases as oxygen pressure
increases. For excitation with an electron beam, the
opposite effect is observed – the lower the oxygen
pressure, the lower the luminescence signal. The
experimental results are explained in terms of
luminescence centers being distorted lattice sites close to
vacancies.

Proceedings of IEEE Sensors 2009

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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

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