La0.4Gd1.6Zr2O7:0.1%Pr transparent sintered ceramic – a wide-range luminescence thermometer†
Sintered transparent ceramics, presenting extraordinary resistance to thermal shocks, incomparably larger than glasses, glass ceramics, and single crystals, maybe valuable luminescence thermometers especially for high-temperature applications. The literature on that subject is, however, very much limited at present. In this paper, the performance of La0.4Gd1.6Zr2O7:0.1%Pr3+ sintered transparent ceramics as a luminescence thermometer was investigated. Temperature dependence of the intensity ratio of emissions from 3P0 and 1D2 levels of the Pr3+ activator was found useful to measure temperature with reasonable relative sensitivity and accuracy over the 15–650 K range – one of the broadest achievable up to date. Time-resolved spectroscopy enabled distinct emissions from 1D2 and 3P0 in the red part of the spectrum. This allowed achieving an impressive relative sensitivity of the La0.4Gd1.6Zr2O7:0.1%Pr luminescence thermometer which exceeded 0.81% K−1 at 650 K.