ZIFs crystals are porous materials with high chemical and thermal stabilities (up to 400 o C). They have similar properties to porous MOFs with a full exposition of imidazole-based ligand edges and faces . ZIFs have the potential to improve several applications such as biomedical applications , gene delivery , biomedicine , environmental , and energybased applications . They are also promising materials for gas separation/storage. ZIF-8 (Zn-based ZIFs) was reported as a colorimetric sensor for the simple detection of CO2 .