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Proton exchange membrane (PEM) is one of the core materials which were widely used in the field of fuel cells (FCs). In recent years, the metal organic frameworks (MOFs) and polymer composite membranes as tunable proton-conducting materials have showed great potential in this field. Herein, a Cu(II)-based metal organic framework (Cu-MOF) with acid/base stability was introduced into poly(vinylpyrrolidone)/poly(vinylidene fluoride) (PVP/PVDF, PP) to fabricate hybrid membranes(Cu-MOF@PP-X, where X is the % Cu-MOF content). The effects of Cu-MOF loading amounts on the conductive behavior of Cu-MOF@PP-X composites have been documented. It is worth noting that Cu-MOF@PP-50 exhibited the proton conductivity up to 4.36 ​× ​10−4 ​S ​cm−1 at 353 ​K and 98% relative humidity (RH). In addition, the value of proton conduction is about two orders of magnitude higher than that of the parent Cu-MOF (1.91 ​× ​10−6 ​S ​cm−1). This work contributes to driving further advances of MOF/polymer composites in proton-conducting apparatus. [Display omitted] • A Cu-MOF with acid/base stability was introduced into polymers (PVP/PVDF, PP) to fabricate hybrid membranes. • The effects of Cu-MOF loading amounts on the conductive behavior of Cu-MOF@PP-X composites have been documented. • Cu-MOF@PP-50 exhibited a super protonic conductivity up to 4.36 ​× ​10−4 ​S ​cm−1 at 353 ​K and 98% relative humidity (RH). • The value of proton conduction of Cu-MOF@PP-50 is about two orders of magnitude higher than that of the parent Cu-MOF. [ABSTRACT FROM AUTHOR]

[Display omitted] • M(AIP)(BPY) 0.5 (M = Co, Ni, and Zn) showed efficient C 3 H 6 /C 3 H 8 separation. • The separation mechanism was based on the thermodynamic-kinetic synergetic effect. • Ni(AIP)(BPY) 0.5 had the highest C 3 H 6 /C 3 H 8 uptake ratio of 4.26 at 298 K and 1 bar. Efficient adsorption separation of propylene (C 3 H 6) and propane (C 3 H 8) can largely lower the energy consumption compared to the current energy-intensive cryogenic distillation. Herein, we report an isoreticular family of pillar-layer metal–organic frameworks (MOFs), M(AIP)(BPY) 0.5 (M = Co, Ni, and Zn), for efficient C 3 H 6 /C 3 H 8 separation by simultaneously exploiting thermodynamic and kinetic effects, circumventing disadvantages of each separation mechanism. The three MOFs feature an open metal site for each metal node and uniform but narrow one-dimensional (1D) channels, offering strong binding sites toward C 3 H 6 via π-complexations while obstructing the diffusion of bulkier C 3 H 8. The Ni-MOF shows the best separation performance based on the highest thermodynamic and kinetic C 3 H 6 /C 3 H 8 selectivities, further verified by computational simulations. Ni(AIP)(BPY) 0.5 has a moderate C 3 H 6 uptake of 1.94 mmol/g but a remarkably high C 3 H 6 /C 3 H 8 uptake ratio of 4.26 at 298 K and 1 bar. Efficient C 3 H 6 /C 3 H 8 separation, good recyclability, moisture and water stability of Ni(AIP)(BPY) 0.5 are confirmed. [ABSTRACT FROM AUTHOR]

A new 3D anionic metal-organic framework material, namely, [Me 2 NH 2 ] 2 [Cd 3 (L)]·2H 2 O (1 , H 4 L ​= ​2,5′-di(3′,5′-dicarboxylphenyl)pyridine) has been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction, PXRD, thermogravimetric analysis and proton conduction investigation. In 1 , the adjacent Cd(II) ions are joined to form a trinuclear [Cd 3 (COO) 8 ] secondary building unit (SBU) by eight bridging carboxylate groups of L4− ligands. The trinuclear [Cd 3 (COO) 8 ] SBUs are connected by L4− ligands into a 3D (4,8)-connected framework with 1D channels. Most interestingly, due to the guest [Me 2 NH 2 ]+ cations, water molecules and carboxylates sites are lined the pore channels, 1 possesses a remarkable proton conductivity of 1.12 ​× ​10−1 ​S ​cm−1 ​at 60 ​°C and 98% RH, which is comparable to commercially available Nafion. The mechanism of proton conduction was also well discussed. A new 3D anionic metal-organic framework material, namely, [Me 2 NH 2 ] 2 [Cd 3 (L)]·2H 2 O (1 , H 4 L ​= ​2,5′-di(3′,5′-dicarboxylphenyl)pyridine) has been synthesized under solvothermal conditions and characterized by single crystal X-ray diffraction, PXRD, thermogravimetric analysis and proton conduction investigation. Compound 1 exhibits a (4,8)-connected 3D network based on trinuclear [Cd 3 (COO) 8 ] cluster units with excellent water stability. It's worth noting that the value of proton conductivity of 1 reaches 1.12 ​× ​10−1 ​S ​cm−1 ​at 60 ​°C and 98% RH which is comparable to most of the dramatic proton conducting MOFs materials. The activation energy (E a) of 1 is 0.376 ​eV estimated by Arrhenius equation. [Display omitted] • A trinuclear Cd-based 3D (4,8)-connected anionic metal-organic framework were synthesized. • The [Me 2 NH 2 ]+ ​cations, H 2 O and host carboxylates could construct continuous proton-conducting pathways. • The MOF exhibited a remarkable proton conductivity of 1.12×10-1 ​S cm-1 ​at 60°C and 98% RH. [ABSTRACT FROM AUTHOR]