Seoane B, Dikhtiarenko A, Mayoral A, Tellez C, Coronas J, Kapteijn F, Gascon J
Catalysis Engineering , ChemE , Delft University of Technology , Julianalaan 136 , 2628 BL Delft , The Netherlands . Email:
Chemical and Environmental Engineering Department and Nanoscience Institute of Aragon (INA) , Universidad de Zaragoza , Mariano Esquillor , Edificio I+D , 50018 , Zaragoza , Spain ; Advanced Microscopy Laboratory (LMA) , Nanoscience Institute of Aragon (INA) , Universidad de Zaragoza , Mariano Esquillor , Edificio I+D , 50018 , Zaragoza , Spain.
CrystEngComm. 2015 Feb 21;17(7):1693-1700. doi: 10.1039/c4ce02324b. Epub 2015 Jan 23.
The effect of synthesis pH and HO/EtOH molar ratio on the textural properties of different aluminium trimesate metal organic frameworks (MOFs) prepared in the presence of the well-known cationic surfactant cetyltrimethylammonium bromide (CTAB) at 120 °C was studied with the purpose of obtaining a MOF with hierarchical pore structure. Depending on the pH and the solvent used, different topologies were obtained (namely, MIL-96, MIL-100 and MIL-110). On the one hand, MIL-110 was obtained at lower temperatures than those commonly reported in the literature and without additives to control the pH; on the other hand, MIL-100 with crystallite sizes as small as 30 ± 10 nm could be easily synthesized in a mixture of HO and EtOH with a HO/EtOH molar ratio of 3.4 at pH 2.6 in the presence of CTAB. The resulting material displays a hierarchical porosity that combines the microporosity from the MOF and the non-ordered mesopores defined in between the MOF nanoparticles. Interestingly, the maximum of the pore size distribution could be varied between 3 and 33 nm. Finally, at pH 2.5 and using water as a solvent, platelets of MIL-96, a morphology never observed before for this MOF, were synthesized with a (001) preferential crystal orientation, the (001) plane running parallel to the bipyramidal cages of the MIL-96 topology.
研究了合成pH值和HO/EtOH摩尔比对在120℃下于著名的阳离子表面活性剂十六烷基三甲基溴化铵（CTAB）存在下制备的不同偏苯三酸铝金属有机框架（MOF）的结构性质的影响，目的是获得具有分级孔结构的MOF。根据pH值和所用溶剂的不同，获得了不同的拓扑结构（即MIL-96、MIL-100和MIL-110）。一方面，MIL-110是在比文献中通常报道的温度更低且无添加剂控制pH值的条件下获得的；另一方面，在CTAB存在下，于pH 2.6时在HO和EtOH的摩尔比为3.4的混合物中，可以轻松合成微晶尺寸小至30±10 nm的MIL-100。所得材料呈现出分级孔隙率，它结合了MOF的微孔和MOF纳米颗粒之间定义的无序中孔。有趣的是，孔径分布的最大值可以在3至33 nm之间变化。最后，在pH 2.5且以水为溶剂的条件下，合成了具有（001）优先晶体取向的MIL-96片状晶体，这种MOF的这种形态以前从未观察到过，（001）平面平行于MIL-96拓扑结构的双锥笼。
