Fig. 1 (a) XRD patterns of the as-synthesized ZIF-8 samples and the simulated one from ZIF-8 crystal structure data excluding guest species;4 (b, c) TEM images of the as-synthesized samples. The inset of (b) is the electron diffraction pattern; (d) photograph of a light blue stable suspension of the as-synthesized ZIF-8 nanocrystals dispersed in methanol.