Dual-Emitting\nUiO-66(Zr&Eu) Metal–Organic Framework Films for Ratiometric\nTemperature Sensing

Abstract

A novel\ndual-emitting metal–organic framework based on Zr and Eu, named\nas UiO-66­(Zr&Eu), was built using a clever strategy based on secondary\nbuilding units. With the use of polymers, the obtained UiO-66­(Zr&Eu)\nwas subsequently deposited as thin films that can be utilized as smart\nthermometers. The UiO-66­(Zr&Eu) polymer films can be used for\nthe detection of temperature changes in the range of 237–337\nK due to the energy transfer between the lanthanide ions (Eu in clusters)\nand the luminescent ligands, and the relative sensitivity reaches\n4.26% K^–1 at 337 K. Moreover, the sensitivity can\nbe improved to 19.67% K^–1 by changing the film thickness.\nIn addition, the temperature-sensing performance of the films is superior\nto that of the powders, and the sensor can be reused 3 times without\nloss of performance.