A Luminescent Metal–Organic Framework Thermometer with Intrinsic Dual Emission from Organic Lumophores

Abstract

A new mixed-ligand metal-organic framework (MOF), ZnATZ-BTB, has been constructed as a luminescent ratiometric thermometer by making use of the intrinsic dual emission at cryogenic temperatures. Its twofold interpenetrated network promotes the Dexter energy transfer (DET) between the mixed organic lumophores. The temperature-dependent luminescent behavior arises from the thermal equilibrium between two separated excited states coupled by DET, which is confirmed by Boltzmann distribution fitting. The small excited-state energy gap allows ZnATZ-BTB to measure and visualize cryogenic temperatures (30-130 K) with significantly high relative sensitivity (up to 5.29% K(-1) at 30 K). Moreover, it is the first example of a ratiometric MOF thermometer the dual emitting sources of which are widely applicable mixed organic ligands, opening up new opportunities for designing such devices.

Inherently Eu2+/Eu3+ Codoped Sc2O3 Nanoparticles as High‐Performance Nanothermometers

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Recent Progress in Metal-Organic Framework Based Fluorescent Sensors for Hazardous Materials Detection

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Thermo-responsive light-emitting metal complexes and related materials

“…As an example of 3D thermo-responsive luminescent Zn(II) MOFs, a mixed-ligand MOF ZnATZ-BTB (ATZ = 5-amino-1-Htetrazolate, BTB = 1,3,5-tris(4-carboxyphenyl)-benzene) has been constructed by Wu and coworkers to function as a ratiometric thermometer at cryogenic temperatures. 134 31). 135 Upon heating or cooling, green and blue emissions of 39 were reversibly switched, in which the ESIPT process triggered by the interconversion of hydrated and dehydrated crystalline phases was proposed to play a significant role.…”