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Title: A New Electrically Conducting Metal–Organic Framework Featuring U-Shaped cis-Dipyridyl Tetrathiafulvalene Ligands
A new electrically conducting 3D metal-organic framework (MOF) with a unique architecture was synthesized using 1,2,4,5-tetrakis-(4-carboxyphenyl)benzene (TCPB) a redox-active cis -dipyridyl-tetrathiafulvalene ( Z -DPTTF) ligand. While TCPB formed Zn 2 (COO) 4 secondary building units (SBUs), instead of connecting the Zn 2 -paddlewheel SBUs located in different planes and forming a traditional pillared paddlewheel MOF, the U-shaped Z -DPTTF ligands bridged the neighboring SBUs formed by the same TCPB ligand like a sine-curve along the b axis that created a new sine -MOF architecture. The pristine sine -MOF displayed an intrinsic electrical conductivity of 1 × 10 −8  S/m, which surged to 5 × 10 −7  S/m after I 2 doping due to partial oxidation of electron rich Z -DPTTF ligands that raised the charge-carrier concentration inside the framework. However, the conductivities of the pristine and I 2 -treated sine -MOFs were modest possibly because of large spatial distances between the ligands that prevented π-donor/acceptor charge-transfer interactions needed for effective through-space charge movement in 3D MOFs that lack through coordination-bond charge transport pathways.  more » « less
Award ID(s):
1809092 1660329
PAR ID:
10300781
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
Frontiers in Chemistry
Volume:
9
ISSN:
2296-2646
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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