Stacking Lanthanide-MOF Thin Films to Yield Highly Sensitive Optical Thermometers

Abstract

Easy-to-integrate, remote read-out thermometers with fast response are of huge interest in numerous application fields. In the context of optical read-out devices, sensors based on the emission of lanthanides (Eu(III), Tb(III)) are particularly promising. Here, by using a layer-by-layer (LbL) approach in the liquid-phase epitaxy process, a series of continuous, low-thickness lanthanide-MIL-103 SURMOFs were fabricated to yield highly sensitive thermometers with optical readout. These Ln-SURMOFs exhibit remarkable temperature-sensing photoluminescence behavior, which can be read out using the naked eye. High transmittance is realized as well by precisely controlling the film thickness and the quality of these Ln-SURMOF thermometers. Moreover, we demonstrate that the thermal sensitivity can be improved in the temperature regime above 120 K, by controlling the energy transfer between Tb(III) and Eu(III). This performance is achieved by employing a sophisticated supramolecular architecture, namely MOF-on-MOF heteroepitaxy.

Achieving high-sensitivity dual-mode optical thermometry via phonon-assisted cross-relaxation in a double-perovskite structured up-conversion phosphor

“…For UC luminescent materials used in optical thermometry, high-quality matrix crystals are one of the key elements to achieve accurate and efficient optical thermometers. 14–18 Fluoride matrix crystals (such as NaYF 4 , SrF 2 , LuF 3 , etc .) normally exhibit efficient UC luminescence due to their low phonon energy.…”

Hypersensitive ratiometric temperature sensing in a bimetallic lanthanide metal–organic framework

“…4–6 Lanthanide metal–organic frameworks (Ln-MOFs), as an important branch of metal–organic frameworks with enormous potential, have attracted considerable attention due to the inherent characteristics and remarkable luminescence properties of lanthanide ions. 7–17 Eu 3+ and Tb 3+ ions are the most widely used lanthanide ions in photoluminescence research, 18–26 which can emit strong characteristic red or green luminescence when excited by energy transfer from ligands to lanthanide ions under ultraviolet radiation. Because of the similarity of both chemical properties and electronic structures, the lanthanide ions can be easily replaced with each other to obtain hybrid Ln-MOFs, 27 in which each lanthanide ion can maintain its own characteristic emission.…”