Smart Tetraphenylethene‐Based Luminescent Metal–Organic Frameworks with Amide‐Assisted Thermofluorochromics and Piezofluorochromics. Issue 16 (31st March 2022)

• Record Type: Journal Article
• Authors: Zhu, Zhong‐Hong; Bi, Changjiang; Zou, Hua‐Hong; Feng, Guangxue; Xu, Shuping; Tang, Ben Zhong
• Is Part Of: Advanced science. Volume 9:Issue 16(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-03-31
• Subjects: aggregation‐induced emission -- host–guest interactions -- luminescent metal–organic frameworks -- piezofluorochromics -- thermofluorochromics; Science -- Periodicals; 505
• DOI: 10.1002/advs.202200850
• Languages: English
• ISSNs: 2198-3844

Abstract

Abstract: Luminescent metal–organic frameworks (MOFs) are appealing for the design of smart responsive materials, whereas aggregation‐induced emission (AIE) fluorophores with twisted molecular rotor structure provide exciting opportunities to construct MOFs with new topology and responsiveness. Herein, it is reported that elongating AIE rotor ligands can render the newly formed AIE MOF (ZnETTB) (ETTB = 4', 4''', 4''''', 4'''''''‐(ethene‐1, 1, 2, 2‐tetrayl)tetrakis(([1, 1'‐biphenyl]‐3, 5‐dicarboxylic acid))) with more elasticity, more control for intramolecular motion, and specific amide‐sensing capability. ZnETTB shows specific host–guest interaction with amide, where N, N ‐diethylformamide (DEF), as an example, is anchored through CH···O and CH··· π bonds with Zn cluster and ETTB 8− ligand, respectively. DEF anchoring reduces both the distortion level and the intramolecular motions of ETTB 8− ligand to lead a blueshifted and intensified emission for DEF ∈ ZnETTB. Moreover, amide anchoring also affords the DEF ∈ ZnETTB with the excellent thermofluorochromic behavior, and further increases the piezofluorochromic sensitivity at low‐pressure ranges on the basis of its elastic framework. This work is one of the rare examples of amide‐responsive smart materials, which shall shed new lights on design of smart MOFs with twisted AIE rotors for further sensing and detection applications. Abstract : It is reported that elongating aggregation‐induced emission (AIE) rotor ligand can render the newly formed AIE metal–organic framework (MOF) (ZnETTB) with more elasticity, more control for intramolecular motion, and specific amide‐sensing capability. Amide anchoring further yields the resultant MOF with thermofluorochromic behavior and improved piezofluorochromic sensitivity.