Respiration Drives Dynamic Metal-Organic Framework for Smart Photoresponse to Volatile Toxic Vapors and Their Photodynamic Sterilization.

Abstract

Using aggregation-induced emission luminous (AIEgens) containing dynamic molecular rotor structures as linkers to construct flexible smart luminescent metal-organic frameworks (MOFs) has become a transformative approach to constructing artificial intelligence color-changing materials. Herein, 4',4″,4'″,4″″-(ethene-1,1,2,2-tetrayl)tetrabiphenyl-4-carboxylic acid (H₄TPPE) is selected as a linker, and octahedral Zr₆O₄(OH)₈(H₂O)₄ cluster are used as secondary building unit (SBU) to construct the first smart luminescent MOF (Zr-TPE-MOF) that can be driven by CH₂Cl₂ or CH₃COOH vapor for respiration. It is worth noting that Zr-TPE-MOF can absorb trace amounts of CH₂Cl₂ or CH₃COOH vapor into the pores through respiration and shows a blue shift of the emission wavelength up to 479 nm and an increase of emission intensity by nearly three times. In addition, the thermochromic behavior of Zr-TPE-MOF is not obvious in the temperature range of 80-350 K, but it has obvious thermofluorochromics behavior in the temperature range of 350-470 K. Zr-TPE-MOF showed highly sensitive and visualized smart photoresponse to the highly toxic Cr₂O₇ ^2-, with a detection limit as low as 7.49 µm. Benefiting from the porous framework structure and organic-inorganic hybrid characteristics of Zr-TPE-MOF, it has excellent ROS generation ability and has excellent application prospects in photodynamic sterilization and rapid degradation of colored dyes.