铬-对苯二甲酸MOF的框架异构:MIL⁃88B(Cr)和MIL⁃101(Cr)

Framework Isomerism in Chromium⁃Benzenedicarboxylate MOF:MIL⁃88B(Cr)and MIL⁃101(Cr)

可以通过简单地控制乙酸浓度的方法,在相似的水热合成条件下合成2种同一家族的金属有机框架材料(MOFs):MIL-88B(Cr)和MIL-101(Cr)。在相对较低的乙酸浓度下,可以得到平均粒径为100 nm的MIL-101(Cr),并拥有很高的BET比表面积(3543 m^2·g^-1)。而在相对较高的乙酸浓度下,则可得到另一种具有“呼吸”特性结构的MOF——MIL-88B(Cr)。利用粉末X射线衍射、扫描电镜、N2吸附-脱附分析、热重分析等对它们的结构、形貌、孔隙率等性质做了详细的分析。

Two metal-organic frameworks(MOFs)of the same family,MIL-88B(Cr)and MIL-101(Cr),can be prepared under similar hydrothermal synthetic conditions via adjusting the concentration of acetic acid.Nanocrystals of MIL-101(Cr)with 100 nm average size and excellent SBET(3543 m^2·g^-1)were obtained at relatively lower concentrations of acetic acid,while at higher concentrations the micro-sized MIL-88B(Cr)product with‘breathe’structure was formed.The products were characterized by powder X-ray diffraction,scanning electron microscopy,nitrogen physisorption measurement and thermal gravimetric analysis.