Long-Term Photostability in Terephthalate Metal-Organic Frameworks.

Prolonged (weeks) UV/Vis irradiation under Ar of UiO-66(Zr), UiO66 Zr-NO2 , MIL101 Fe, MIL125 Ti-NH2 , MIL101 Cr and MIL101 Cr(Pt) shows that these MOFs undergo photodecarboxylation of benzenedicarboxylate (BDC) linker in a significant percentage depending on the structure and composition of the material. Routine characterization techniques such as XRD, UV/Vis spectroscopy and TGA fail to detect changes in the material, although porosity and surface area change upon irradiation of powders. In contrast to BCD-containing MOFs, zeolitic imidazolate ZIF-8 does not evolve CO2 or any other gas upon irradiation.