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Title: Fluorous Metal–Organic Frameworks and Nonporous Coordination Polymers as Low‐κ Dielectrics
Abstract A fluorous metal–organic framework [Cu(FBTB)(DMF)] (FMOF‐3) [H2FBTB = 1,4‐bis(1‐H‐tetrazol‐5‐yl)tetrafluorobenzene] and fluorous nonporous coordination polymer [Ag2(FBTB)] (FN‐PCP‐1) are synthesized and characterized as for their structural, thermal, and textural properties. Together with the corresponding nonfluorinated analogues lc‐[Cu(BTB)(DMF)] and [Ag2(BTB)], and two known (super)hydrophobic MOFs, FMOF‐1 and ZIF‐8, they have been investigated as low‐dielectric constant (low‐κ) materials under dry and humid conditions. The results show that substitution of hydrogen with fluorine or fluoroalkyl groups on the organic linker imparts higher hydrophobicity and lower polarizability to the overall material. Pellets of FMOF‐1, FMOF‐3, and FN‐PCP‐1 exhibit κ values of 1.63(1), 2.44(3), and 2.57(3) at 2 × 106Hz, respectively, under ambient conditions, versus 2.94(8) and 3.79(1) for lc‐[Cu(BTB)(DMF)] and [Ag2(BTB)], respectively. Such low‐κ values persist even upon exposure to almost saturated humidity levels. Correcting for the experimental pellet density, the intrinsic κ for FMOF‐1 reaches the remarkably low value of 1.28, the lowest value known to date for a hydrophobic material.  more » « less
Award ID(s):
1726652
PAR ID:
10460521
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Advanced Functional Materials
Volume:
29
Issue:
40
ISSN:
1616-301X
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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