Highly sensitive multiparametric luminescent thermometer for biologically-relevant temperatures based on Mn4+, Ln3+ co-doped SrTiO3 nanocrystals

Abstract

The constant striving to improve the quality of thermal imaging with the use of luminescent thermometers imposes the search for new materials with better and better thermometric properties. The facility in the modulation of the spectroscopic properties of transition metal doped materials makes them particularly attractive for this type of application. Therefore, in response to this expectation, in this manuscript we report the novel SrTiO3:Mn4+ nanocrystals as a thermographic phosphor of extraordinary thermometric properties in the biologically relevant temperatures. The high relative sensitivity of the SrTiO3:Mn4+ nanocrystals to temperature changes in each of the three temperature readout modes presented in this manuscript, namely 8.67%/K at 313 K in the intensity mode, 3.5%/K at 348 K in the lifetime mode and 5.64%/K at 303 K in the ratiometric mode, make this material one of the most promising candidates for highly sensitive temperature imaging.