Expanded porous MOF-505 analogue exhibiting large hydrogen storage capacity and selective carbon dioxide adsorption

摘要

An expanded 4,4-paddlewheel-connected porous MOF-505-type metal-organic framework (MOF), [Cu_2(PDEB)(H_2O)_2]·xS (NJU-Bai12; NJU-Bai represents the Nanjing University Bai group and S represents noncoordinated solvent molecules) has been designed from a nanosized rectangular diisophthalate linker containing alkyne groups 5,5′-(1,4- phenylenedi-2,1-ethynediyl)bis(1,3-benzenecarboxylic acid). This MOF material possesses permanent microporosity with the highest Brunauer-Emmett-Teller surface area of 3038 m~2·g~(-1) and the largest unsaturated total hydrogen storage capacity of 62.7 mg·g~(-1) at 77 K and 20 bar among reported MOF-505 analogues. Additionally, NJU-Bai12 also exhibits excellent carbon dioxide (CO_2) uptake capacity (23.83 and 19.85 mmol·g~(-1) at 20 bar for 273 and 298 K, respectively) and selective gas adsorption properties with CO_2/CH_4 selectivity of 5.0 and CO_2/N_2 selectivity of 24.6 at room temperature.