Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7921448 | Materials Chemistry and Physics | 2018 | 21 Pages |
Abstract
PL of Eu3+ ions was observed under direct excitation at 395â¯nm. PL decay kinetics showed that the luminescence was partially quenched, depending on doping concentrations and ambient atmosphere. At 300â¯Â°C, the PL intensity of all samples systematically responded (with up to 70% change) to changing oxygen content in the O2/N2 mixture at atmospheric pressure. At low doping levels, the dominant factor controlling the PL intensity was an energy transfer from excited PL centers to randomly distributed defects in the ZrO2 lattice. We argue that the charge transfer between the defects and adsorbed oxygen molecules alters the ability of the defects to quench Eu3+ luminescence. At high doping levels, another type of sensor response was observed, where some Eu3+ emitters are effectively switched on or off by the change of ambient gas. A remarkable feature of the studied material is a reversing of the sensor response with the variation of the Nb concentration.
Related Topics
Physical Sciences and Engineering
Materials Science
Electronic, Optical and Magnetic Materials
Authors
Valter Kiisk, Laurits Puust, Hugo Mändar, Peeter Ritslaid, Mihkel Rähn, Ivita Bite, Dzidra Jankovica, Ilmo Sildos, Raivo Jaaniso,