Lite Version|Standard version

To gain access to this content please
Log in via your home Institution.
Log in with your member or subscriber username and password.
Download

It was proved quite recently that luminescence thermometry may benefit from utilizing the 5d → 4f/4f → 4f intensity ratio of Pr3+ transitions. This paper presents a comprehensive study of Lu2(Gex,Si1−x)O5:Pr phosphors in the full range of Ge concentrations (x = 0–1) for luminescence thermometry. Silicon substitution by germanium allows effective management of their thermometric properties through bandgap engineering. The Ge/Si ratio controls the range of temperatures within which the 5d → 4f Pr3+ luminescence can be detected. This, in turn, defines the range of temperatures within which the 5d → 4f/4f → 4f emission intensity ratio can be utilized for thermometry. Altogether, the bandgap engineering allows widening the operating range of thermometers (17–700 K), fine-tunes the range of temperatures with the highest relative sensitivity, and reduces the inaccuracy of the measurements. The kinetics of the 5d → 4f luminescence is also controlled by bandgap engineering and can be also used for luminescence thermometry. The Lu2(Gex,Si1−x)O5:Pr phosphors were, thus, designed as dual-mode luminescence thermometers exploiting either the inter- and intra-configurational intensity ratios or the 5d → 4f decay time. The highest relative thermal sensitivity, 3.54% K−1, was found at 17 K for Lu2(Ge0.75,Si0.25)O5:Pr and at 350 K for Lu2SiO5:Pr and it was combined with a very low (<0.03 K) temperature uncertainty. Herein, we proved that bandgap engineering is a promising and effective approach to developing high-performance luminescence thermometers.

Graphical abstract: Exploiting bandgap engineering to finely control dual-mode Lu2(Ge,Si)O5:Pr3+ luminescence thermometers

Page: ^ Top