In summary, for the first time we r

In summary, for the first time we reported the synthesis ofZIF-8 crystals in pure aqueous solution. It is also the first example of ZIF materials synthesized in pure aqueous solutions. The synthesis method allowed us to make ZIF-8 nanocrystals in a much shorter time with improved product yield compared to the synthesis processes developed in organic media. Thorough stability studies indicated that the porous structure would not collapse during the removal of guest molecules to activate the pores. The product showed excellent thermal and chemical stabilities, and improved hydrothermal stability. We expect the method can stimulate more ZIF materials synthesized in aqueous solution in future studies and thus open up more efficient and economical ways to synthesize these materials.