MgAl2O4:Cr3+ luminescence thermometry probe in the physiological temperatures range

Temperature sensing from the photoluminescence of MgAl2O4:Cr3+ ceramic powder is systematically investigated. Material was prepared by self-propagating high temperature synthesis method. In this host, Cr3+ experiences the strong crystal field, so the overlapping emissions from E-2 and T-4(2) energy levels are observed. Emission and excitation spectra were recorded from 300 K to 540 K. The broad photoluminescence attributed to T-4(2)->(4)A(2) emission gains in intensity with increase in temperature on account of E-2 ->(4)A(2) emission intensity until 460 K when both emissions start quenching. The emissions were separated by deconvolution at each temperature and used for the luminescence intensity ratio temperature readout method. The obtained relative sensitivity exhibited high values in the physiological range, from 3.5 %K-1 at 300 K to 2.9 %K-1 at 330 K, above 2 %K-1 below 400 K and above 1 %K-1 between 400 K and 540 K.

Automated summary

Temperature sensing using photoluminescence of MgAl2O4:Cr3+ ceramic powder was investigated, showing high relative sensitivity in the physiological range. The intensity of emissions changes with temperature, allowing for temperature measurement.