Multifunctional optical thermometry based on the transition metal ions doped down-conversion Gd2ZnTiO6: Bi3+, Mn4+ phosphors

Nowadays, how to improve the accuracy of the temperature sensors has become a common concern of researchers. For this purpose, dual-emitting phosphors have been proposed as a novel optical thermometer because the two discriminate emission centers can avoid the error caused by spectral overlap. Herein, a new ratio-metric luminescent thermometer Gd2ZnTiO6(GZTO):Bi3+, Mn4+ is designed, which exhibits both red and blue luminescence under 375 nm excitation. Based on the different thermal sensitivity of Mn4+ and Bi3+ ions and the energy transfer from Bi3+ to Mn4+ ions, the luminescent thermometer reveals excellent thermal sensitivity (Sr = 2.4% K-1, Sa = 16.8%K-1) and a wide temperature measurement range (313-473 K). Both of them are superior to the most reported materials. In addition, the luminescence intensity of two ions matches the light absorption bands of photosynthetic pigment well, which indicates that GZTO: Bi3+, Mn4+ phosphors also have a great prospect as a plant growth lamp.