Froudas Konstantinos G, Vassaki Maria, Papadopoulos Konstantinos, Tsangarakis Constantinos, Chen Xu, Shepard William, Fairen-Jimenez David, Tampaxis Christos, Charalambopoulou Georgia, Steriotis Theodore A, Trikalitis Pantelis N
Department of Chemistry, University of Crete, Heraklion 71003, Greece.
Department of Chemical Engineering & Biotechnology, University of Cambridge, Philippa Fawcett Drive, Cambridge CB3 0AS, U.K.
J Am Chem Soc. 2024 Apr 3;146(13):8961-8970. doi: 10.1021/jacs.3c12679. Epub 2024 Mar 1.
The chemistry of metal-organic frameworks (MOFs) continues to expand rapidly, providing materials with diverse structures and properties. The reticular chemistry approach, where well-defined structural building blocks are combined together to form crystalline open framework solids, has greatly accelerated the discovery of new and important materials. However, its full potential toward the rational design of MOFs relies on the availability of highly connected building blocks because these greatly reduce the number of possible structures. Toward this, building blocks with connectivity greater than 12 are highly desirable but extremely rare. We report here the discovery of novel 18-connected, trigonal prismatic, ternary building blocks ('s) and their assembly into unique MOFs, denoted as Fe--MOF- (: 1, 2, 3), with hierarchical micro- and mesoporosity. The remarkable is an 18-c supertrigonal prism, with three points of extension at each corner, consisting of triangular (3-c) and rectangular (4-c) carboxylate-based organic linkers and trigonal prismatic [Fe(μ-Ο)(-COO)] clusters. The 's are linked together by an 18-c cluster made of 4-c ligands and a crystallographically distinct Fe(μ-Ο) trimer, forming overall a 3-D (3,4,4,6,6)-c five nodal net. The hierarchical, highly porous nature of Fe--MOF- (: 1, 2, 3) was confirmed by recording detailed sorption isotherms of Ar, CH, and CO at 87, 112, and 195 K, respectively, revealing an ultrahigh BET area (4263-4847 m g) and pore volume (1.95-2.29 cm g). Because of the observed ultrahigh porosities, the H and CH storage properties of Fe--MOF- were investigated, revealing well-balanced high gravimetric and volumetric deliverable capacities for cryoadsorptive H storage (11.6 wt %/41.4 g L, 77 K/100 bar-160 K/5 bar), as well as CH storage at near ambient temperatures (367 mg g/160 cm STP cm, 5-100 bar at 298 K), placing these materials among the top performing MOFs. The present work opens new directions to apply reticular chemistry for the construction of novel MOFs with tunable porosities based on contracted or expanded analogues.
金属有机框架材料（MOFs）的化学领域持续迅速拓展，不断涌现出具有多样结构和性质的材料。网状化学方法是将结构明确的建筑模块组合在一起，形成晶体开放框架固体，这极大地加速了新型重要材料的发现。然而，其在MOFs合理设计方面的全部潜力，依赖于高连接性建筑模块的可得性，因为这些模块能大幅减少可能结构的数量。为此，连接性大于12的建筑模块非常理想，但极为罕见。我们在此报告发现了新型的18连接三角棱柱形三元建筑模块（‘s），并将它们组装成独特的MOFs，记为Fe--MOF-（: 1, 2, 3），具有分级的微孔和介孔结构。显著的是一个18连接的超三角棱柱，每个角有三个延伸点，由基于三角形（3连接）和矩形（4连接）羧酸盐的有机连接体以及三角棱柱形[Fe(μ-Ο)(-COO)]簇组成。这些‘s通过由4连接配体和一个晶体学上不同的Fe(μ-Ο)三聚体构成的18连接簇连接在一起，整体形成一个三维（3,4,4,6,6）连接的五节点网络。通过分别记录87 K、112 K和195 K下Ar、CH和CO的详细吸附等温线，证实了Fe--MOF-（: 1, 2, 3）具有分级、高度多孔的性质，显示出超高的BET面积（4263 - 4847 m g）和孔体积（1.95 - 2.29 cm g）。由于观察到的超高孔隙率，对Fe--MOF-的H和CH储存性能进行了研究，结果表明其在低温吸附H储存方面具有良好平衡的高重量和体积可释放容量（11.6 wt %/41.4 g L，77 K/100 bar - 160 K/5 bar），以及在近环境温度下的CH储存性能（367 mg g/160 cm STP cm，298 K时5 - 100 bar），使这些材料跻身性能最佳的MOFs之列。本工作为应用网状化学构建基于收缩或扩展类似物的具有可调孔隙率的新型MOFs开辟了新方向。
