The coordinatively unsaturated sites in MIL‐101, Cr3(F,OH)(H2O)2O[(O2C)‐C6H4‐(CO2)]3⋅n H2O (n≈25), having zeotypic giant pores can be selectively functionalized in a way differing from that of mesoporous silica. Metal–organic frameworks, grafted with ethylenediamine or diethylenetriamine on the unsaturated CrIII sites of MIL‐101, exhibit remarkably high activities in the Knoevenagel condensation relative to that of the mesophase.
Hierarchically ordered mesocellular mesoporous silicas (HMMS) were swiftly synthesized using P123 and sodium silicate as a silica source within an hour by applying microwave irradiation without pore expander. The XRD, TEM and BET studies demonstrated that materials as-synthesized and calcined have the hierarchically ordered mesocellular structure with two different sizes about 10 nm and 30 nm pores having a minimized micropore volume compared with conventional hydrothermal method. Moreover, the HMMS sample prepared by microwave-assisted hydrothermal method had higher surface area than that of conventional hydrothermal method. The variation of the pore size and morphology of mesocellular structure varied with the aging time.
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