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Two-dimensional graphitic metal-organic frameworks (GMOF) often display impressive electrical conductivity chiefly due to efficient through-bond in-plane charge transport, however, less efficient out-of-plane conduction across the stacked layers creates large disparity between two orthogonal conduction pathways and dampens their bulk conductivity. To address this issue and engineer higher bulk conductivity in 2D GMOFs, we have constructed via an elegant bottom-up method the first π-intercalated GMOF (iGMOF1) featuring built-in alternate π-donor/acceptor (π-D/A) stacks of Cu II -coordinated electron-rich hexaaminotriphenylene (HATP) ligands and non-coordinatively intercalated π-acidic hexacyano-triphenylene (HCTP) molecules, which facilitated out-of-plane charge transport while the hexagonal Cu 3 (HATP) 2 scaffold maintained in-plane conduction. As a result, iGMOF1 attained an order of magnitude higher bulk electrical conductivity and much smaller activation energy than Cu 3 (HATP) 2 (σ=25 vs. 2 S m -1 , E a =36 vs. 65 meV), demostrating that simultaneous in-plane (through-bond) and out-of-plane (through πD/A stacks) charge transport can generate higher electrical conductivity in novel iGMOFs., (© 2023 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH.)

Two‐dimensional graphitic metal–organic frameworks (GMOF) often display impressive electrical conductivity chiefly due to efficient through‐bond in‐plane charge transport, however, less efficient out‐of‐plane conduction across the stacked layers creates large disparity between two orthogonal conduction pathways and dampens their bulk conductivity. To address this issue and engineer higher bulk conductivity in 2D GMOFs, we have constructed via an elegant bottom‐up method the first π‐intercalated GMOF (iGMOF1) featuring built‐in alternate π‐donor/acceptor (π‐D/A) stacks of CuII‐coordinated electron‐rich hexaaminotriphenylene (HATP) ligands and non‐coordinatively intercalated π‐acidic hexacyano‐triphenylene (HCTP) molecules, which facilitated out‐of‐plane charge transport while the hexagonal Cu3(HATP)2 scaffold maintained in‐plane conduction. As a result, iGMOF1 attained an order of magnitude higher bulk electrical conductivity and much smaller activation energy than Cu3(HATP)2 (σ=25 vs. 2 S m−1, Ea=36 vs. 65 meV), demostrating that simultaneous in‐plane (through‐bond) and out‐of‐plane (through πD/A stacks) charge transport can generate higher electrical conductivity in novel iGMOFs. [ABSTRACT FROM AUTHOR]

Owing to their highly ordered crystalline structures and ease of introducing different electroactive meta ions and ligands, metal–organic frameworks (MOFs) have emerged as promising electrical and ion conducting materials. In this minireview, we highlighted recent advances in guest-induced electronic and ionic conductivity of MOFs, which are otherwise insulators or poor conductors. Examples of conductivity enhancement upon guest-induced framework oxidation or reduction, π-donor/acceptor stack formation, crosslinking of coordinatively unsaturated nodes, and binding of mobile Li+ and Mg2+ with the MOFs are discussed. [ABSTRACT FROM AUTHOR]

Two luminescent MOFs, Zn-NDC and Cd-NDC (NDC = 2,6-naphthalenedicarboxylate), which are capable of sensing 2,4,6-trinitrophenol (TNP) and similar explosives and mutagens, are reported. Of these two MOFs, Zn-NDC shows better response in sensing nitroaromatics like TNP and 4-nitrobenzoic acid (4-NBA). Compared to Zn-NDC, Cd-NDC is more selective in the detection of explosive and pollutant nitroaromatics (epNACs). Cd-NDC is a selective TNP sensor over several other tested epNACs: 2,6-dinitrotoluene (2,6-DNT), nitrobenzene (NB), 4-NBA, 1,3-dinitrobenzene (1,3-DNB), 3,4-dinitrotoluene (3,4-DNT), and 2,4,6-trinitrotoluene (TNT). For both d10-NDC MOFs, TNP sensitivity is supported by fluorescence quenching. The experiments have been carried out with deionized water as well as various other environmental water specimens collected from several parts of West Bengal, India. Spectroscopic results are further supported by theoretical DFT calculations. [ABSTRACT FROM AUTHOR]

A non-interpenetrated square grid metal–organic framework (MOF) comprised of octahedral Zn(ii) ions and linear N,N′-di(4-pyridyl)-1,4,5,8-naphthalenediimide (DPNDI) ligands was formed in the presence of noncoordinating perchlorate counterions that occupied the cavities of the porous network by forming CH…anion hydrogen bonds with DPNDI ligands, whereas a linear coordination polymer was obtained when Zn(ii)-coordinated nitrate ions were present as counterions. [ABSTRACT FROM AUTHOR]