Ma Shengqian, Simmons Jason M, Sun Daofeng, Yuan Daqiang, Zhou Hong-Cai
Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 S. Cass Avenue, Argonne, Illinois 60439, USA.
Inorg Chem. 2009 Jun 15;48(12):5263-8. doi: 10.1021/ic900217t.
Solvothermal assembly of 5,5'-(9,10-anthracenediyl)di-isophthalate (H(4)adip) with in situ-generated dicopper and diiron paddlewheel secondary building units (SBUs) afforded two porous metal-organic frameworks (MOFs), designated as PCN-14 and PCN-15, respectively. The two MOFs crystallize in different structures, characterized by a difference in the dihedral angles between the anthracene and the phenyl rings of the adip ligand. PCN-14 retains permanent porosity under dehydration and contains nanoscopic cages while PCN-15 contains only one-dimensional hexagonal channels along the (0 0 1) direction which require solvent stabilization. The aromaticity of the anthracene rings of the adip ligand in conjunction with the nanoscopic cages grants PCN-14 high excess hydrogen adsorption capacity of 2.70 wt % at 77 K, 760 Torr (4.42 wt % at saturation), as well as high hydrogen affinity of 8.6 kJ/mol at low H(2) coverage. These values are compared to other tetracarboxylate-derived MOFs to better understand the role of the aromatic rings in hydrogen adsorption.
5,5'-（9,10-蒽二基）二间苯二甲酸（H(4)adip）与原位生成的二铜和二铁桨轮二级构筑单元（SBUs）通过溶剂热组装得到了两种多孔金属有机框架（MOFs），分别命名为PCN-14和PCN-15。这两种MOFs具有不同的晶体结构，其特征在于蒽与adip配体的苯环之间的二面角存在差异。PCN-14在脱水后保留了永久孔隙率，并含有纳米级笼状结构，而PCN-15仅沿(0 0 1)方向包含一维六边形通道，需要溶剂稳定化。adip配体的蒽环的芳香性与纳米级笼状结构相结合，使PCN-14在77 K、760 Torr（饱和时为4.42 wt%）下具有2.70 wt%的高过量氢吸附容量，以及在低H(2)覆盖率下具有8.6 kJ/mol的高氢亲和力。将这些值与其他四羧酸衍生的MOFs进行比较，以更好地理解芳香环在氢吸附中的作用。
