Ln-MOF and its hydrogel composite Ln-MOF@PVA for dual-luminescence ratiometric temperature sensing.

Dual-emitting luminescent MOF Eu 0.05 Y 0.95 -PTC and its hydrogel Eu 0.05 Y 0.95 -PTC@PVA-8 were used for sensing temperature over a temperature range from 303 to 383 K with high relative sensitivities and good recyclability. [Display omitted] • Eu 0.05 Y 0.95 -PTC shows stability under both weakly acidic and alkaline conditions and multiband luminescence. • Eu 0.05 Y 0.95 -PTC@PVA-8 showed good structural integrity and retains the temperature-sensing behavior of the MOF in a flexible form. • Both them were used for sensing temperature from 303 to 383 K with high relative sensitivities and good recyclability. In this study, we synthesized a solid solution of MOF, Eu 0.05 Y 0.95 -PTC (H 3 PTC represents 2, 4, 6-pyridine tricarboxylic acid) by hydrothermal reaction, which showed exceptional stability under both weakly acidic and alkaline conditions and multiband luminescence. We further prepared Eu 0.05 Y 0.95 -PTC@PVA hydrogels by immobilizing Eu 0.05 Y 0.95 -PTC into a polyvinyl alcohol (PVA) aqueous solution, which exhibited both the integrity and temperature sensing behavior of the MOF solid solution, alongside excellent mechanical performance. Both Eu 0.05 Y 0.95 -PTC and Eu 0.05 Y 0.95 -PTC@PVA-8 hydrogel displayed temperature sensing capabilities over the range from 303 to 383 K, with relative sensitivities (S r) reaching a maximum value of 1.94 %•K−1 and 0.65 %•K−1 at 383 K, respectively, and good recyclability as well. [ABSTRACT FROM AUTHOR]