Soft-templating Synthesis of Mesoporous Metal-Organic Frameworks with Enhanced Toluene Adsorption Capacity

Metal-organic frameworks (MOFs) commonly have uniform micropores (pore dimension < 2 nm), which may restrict their practical applications involving large molecules. Although quite a little approaches have been developed to prepare mesoporous metal-organic frameworks (meso-MOFs), challenge remains in the preparation of meso-MOFs with controllable/tunable porosity. Here we developed a reliable method to rationally design and synthesize meso-Cu-BTC materials through utilizing a novel amphiphilic surfactant as the template. X-ray diffraction, nitrogen adsorption isotherms and pore size distributions were applied to characterize the attained meso-MOF products, the characterization analyses indicated that the as-synthesized products possess multimodal pore size distribution with micropores and well-ordered mesopores. Moreover, the porosity properties of the meso-Cu-BTC could be systematically controlled by varying the ratio of H2O/EtOH, the amount and type of the template. Owing to the well-order mesoporous structure, the meso-Cu-BTC exhibited high uptake capacity of 152 cm(3).g(-1), about 20% higher as compared with conventional counterpart (128 cm(3).g(-1)) for the capture of toluene. This work provides a new strategy to prepare meso-MOFs with tunable porosity that would fulfill a wide range of applications involving large molecules.