A highly sensitive blue-LED-excitable self-calibrated luminescent thermometer based on Cr3+/Eu3+ Co-doped Al2W3O12

In this work, Al2W3O12:1%Cr3+,2%Eu3+ with two discriminable dual emissive centers is synthesized. Both Eu3+ and Cr3+ ions can be excited efficiently by 465 nm. Photoluminescence excitation (PLE) spectra and photoluminescence (PL) lifetime indicate that there is no energy transfer (ET) between Eu3+ and Cr3+ ions. It is worth noting that the photothermal stability of Eu3+ ions is much better than that of Cr3+ ions. Specifically, the ratio of ICr/IEu decreases linearly with increasing temperature. Therefore, a blue-LED-excitable luminescent thermometer based on Cr3+/Eu3+ co-doped Al2W3O12 is proposed. This developed self-calibrated luminescent temperature sensor possesses the relatively high absolute and relative sensitivity (0.38 K-1 and 2.9% K−1 respectively) as well as good cycle stability among the previously reported TM/Ln-based luminescent; thermometers. These superior features of the developed self-calibrated luminescent thermometer (SCLT) make it a very promising candidate for temperature sensing applications.