Cr3+ ions as an efficient antenna for the sensitization and brightness enhancement of Nd3+, Er3+-based ratiometric thermometer in GdScO3 perovskite lattice
Wojciech Piotrowski, K. Maciejewska, Linda Dalipi, Benoît Fond, Ł. Marciniak
Abstract
Although the technique of luminescence thermometry using luminescence of lanthanide ions (Ln3+) is at a high level of sophistication, its main limitations are the relatively low luminescence brightness and the need for precisely selected optical excitation sources. This is due to their relatively low absorption cross-section and the spectrally narrow nature of the 4–4 f absorption bands. In this work, we propose a strategy that, through exploiting chromium (Cr3+) to Ln3+ energy transfer, circumvent these limitations. It is shown that as the concentration of Cr3+ ions increases up to 15 %, the brightness of a luminescent thermometer based on GdScO3:Nd3+,Er3+ increases 25-fold in respect to the non co-doped counterpart. Additionally, due to the temperature dependence of the Cr3+→Nd3+, Cr3+→Er3+ energy transfer rate, the sensitivity of this thermometer increases threefold. The described studies confirm the beneficial effect of sensitization of Ln3+ ions by Cr3+ ions on the thermometric parameters of this type of luminescent thermometers.