Structural Stability of Metal Organic Framework MOF-177

Metal organic framework MOF-177 is one of the most promising crystalline porous adsorbents for hydrogen adsorption. The effects of oxygen and water on the structural stability of MOF-177 are investigated by X-ray diffraction (XRD) and thermogravimetric analysis (TGA). A MOF-177 sample is exposed to ambient air for 5 weeks and monitored for its structural changes by XRD. The crystal structure of MOF-177 gradually changes from hexagonal to orthogonal; and then to monoclinic in the 5-week period. The crystal structure of MOF-177 is completely destroyed after it is immersed in water. The weight loss of MOF-177 is negligible at temperatures below 330 degrees C in the presence of oxygen. However, MOF-177 totally converts to zinc oxide at 420 degrees C.