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In this work, a bifunctional ligand 2,2′-disulfonic acid benzidine (H2L) was selected, and we adopted a mixed ligand strategy, in which the ligand reacted with 2,2′-bipyridine and 1,10-o-phenanthroline, where two new silver-based coordination polymer materials [Ag2(2,2′-bipy)2L]·H2O (BAg-1) and [Ag2(phen)2L] (BAg-2) were obtained. BAg-1 was zero-dimensional, which could interconnect with one-dimensional hydrogen bonds to form a three-dimensional stacking structure, while BAg-2 was a one-dimensional chain structure, and the one-dimensional chains formed a two-dimensional planar structure through hydrogen bonding between the sulfonic acid group and the amino group. Their proton conductivity reached a high level among the coordination polymers at 98% relative humidity (RH) and 90 °C, where their proton conductivity values were 0.455 × 10−4 S cm−1 (BAg-1) and 1.09 × 10−4 S cm−1 (BAg-2), respectively. Combining their respective single crystal data with the results of Hirshfeld surface analysis, water adsorption experiments, and activation energy calculations, we determined their proton conduction pathways and mechanisms. The results showed that the abundant hydrogen bond chains and hydrogen bond networks co-constructed using sulfonic acid groups, amino groups and crystal water molecules in the framework and numerous uncoordinated sulfonic acid groups as proton carriers in the material were the reasons for efficient proton transfer. [ABSTRACT FROM AUTHOR]

In this work, the two example rare earth‐based metal‐organic frameworks (LaIII‐based MOFs), Eu‐ETTB and Gd‐ETTB, were obtained by self‐assembly. Both materials showed extremely high proton conductivity, with the proton conductivity of Eu‐ETTB being 1.53×10−2 S cm−1 at 98 % relative humidity (RH) and 85 °C and that of Gd‐ETTB being 2.63×10−2 S cm−1 at 98 % RH and 75 °C. This was almost the best performance observed for three‐dimensional porous MOFs without post‐synthetic modification and was based on milder conditions than for most materials. Furthermore, cycle test experiments and continuous work tests showed that both materials had excellent performance both in terms of stability and durability. Water vapor adsorption experiments showed that a large number of water molecules are adsorbed the hydrogen‐bond network's being rebuilt by the adsorbed water molecules in the pore channel and thus optimizing the channels for proton transfer explained the MOF's high performance. [ABSTRACT FROM AUTHOR]

By employing the multifunctional organic ligand, 2-(o-bromo)phenyl-4,5-imidazole dicarboxylic acid (o-H 3 BrPhIDC), two three-dimensional supramolecular complexes, [M(o-H 2 BrPhIDC) 2 (H 2 O) 2 ]·CH 3 CH 2 OH·3H 2 O (M = Zn ( 1 ); Co ( 2 )) have been successfully solvothermally synthesized, and structurally characterized by single crystal X-ray crystallography. Their proton conduction properties have been explored under different temperature and relative humidity (RH). Compounds 1 and 2 indicate high conductivity values of 1.14 × 10 −4  S·cm −1 and 3.11 × 10 −4  S·cm −1 , respectively, at 98% RH and 100 °C. The hydrogen bonding nets inside the two complexes perform a vital function in the resultant conductivity. Variable-temperature and Variable-RH experiments of both compounds reveal that the conductivity values increase with increasing temperature and RH. The proton transfer mechanisms of the complexes have been proposed in terms of the structural analyses, activation energy calculations and PXRD determinations. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks, porous materials, proton conduction, rare earth, tetraphenylethylene Front Cover: Two Novel Three-Dimensional Tetraphenylethylene-Based Rare Earth MOFs with Ultra-High Proton Conductivity and Performance Stability (Chem. Eur. J. 60/2022) Keywords: metal-organic frameworks; porous materials; proton conduction; rare earth; tetraphenylethylene EN metal-organic frameworks porous materials proton conduction rare earth tetraphenylethylene 1 1 1 10/28/22 20221026 NES 221026 B Eu-ETTB and Gd-ETTB were obtained by self-assembly b ; their three-dimensional frameworks provide a channel for proton conduction. [Extracted from the article]