Novel ratiometric optical thermometry based on dual luminescent centers from europium doped LiCa3MgV3O12 phosphor.

In this paper, an optical thermometry strategy based on dual emission centers involving rare earth ions and self-activated host luminescence has been proposed, which can be used to design self-referencing optical thermometer with high temperature sensitivity and signal discriminability. Herein, we prepared non-rare-earth self-activated and rare-earth activated LiCa 3 MgV 3 O 12 (LCMV) phosphors by a conventional high-temperature solid-state reaction method. Their structure, luminescence as well as temperature sensing property have been systematically investigated. In this sample, the emissions of Eu3+ ions and [VO 4 ]3− group have been simultaneously monitored under 335 nm UV light excitation. The FIR of Eu3+ to [VO 4 ]3- shows great temperature sensing property in temperature range from 303 K–523 K,owing to the energy transfer and thermal quenching behavior. The measured maximum absolute and relative temperature sensitivity of this phosphor are 0.011 K−1 and 1.689%K−1, which is remarkably higher than most of luminescent materials reported previously. Meanwhile, the emission peaks of [VO 4 ]3- (475 nm) and Eu3+ (610 nm) provide a good signal discriminability for temperature detection. What's more, the emitting color in the temperature-dependent CIE diagram can highly be influenced by the external temperature and the color coordinate is verified from (0.257, 0.332) to (0.503, 0.342), which can be fitted well with the linear equation. All results indicate that the obtained phosphors not only can be promising materials for optical temperature sensors, but can be used as a color-temperature indicator. [ABSTRACT FROM AUTHOR]