Desorption of dimethylformamide from Zn4O(C8H4O4)3 framework

Both dimethylformamide (DMF) and diethylformamide (DEF) are important solvents for the synthesis of Zn4O(C8H4O4)3 framework (MOF-5). It is generally recognized that DMF molecules can be completely displaced by CH2Cl2 during the synthesis of MOF-5. Herein, however, it was found that the DMF molecules inside the pores of the MOF-5 framework cannot be displaced by CH2Cl2. The desorption of the DMF molecules from the pores, which requires a temperature of 100 °C or above, is the first order with activation energy of 56.38 kJ/mol. In contrast, DEF molecules can be completely displaced by CH2Cl2 during the synthesis of MOF-5, because DEF molecules cannot penetrate into the pores of the MOF-5 paste.

Research highlights▶ DMF molecules inside the pores of the MOF-5 framework cannot be displaced by CH2Cl2. ▶ Desorption of the DMF molecules from the pores of MOF-5 framework requires a temperature of 100 °C or above. ▶ Desorption of the DMF molecules from the pores of the MOF-5 framework is the first order with activation energy of 56.38 kJ/mol. ▶ DEF molecules can be completely displaced by CH2Cl2 during the synthesis of MOF-5, because DEF molecules cannot penetrate into the pores of the MOF-5 paste.