Exploiting In-Situ NMR to Monitor the Formation of a Metal-Organic Framework

The formation processes of metal-organic frameworks are becoming more widely researched using in-situ techniques, although there remains a scarcity of NMR studies in this field. In this work, the synthesis of framework MFM-500(Ni) has been investigated using an in‑situ NMR strategy that provides information on the time-evolution of the reaction and crystallization process. In our in‑situ NMR study of MFM-500(Ni) formation, liquid-phase 1H NMR data recorded as a function of time at 5 fixed temperatures afford qualitative information on the solution-phase processes and quantitative information on the kinetics of crystallization, allowing the activation energies for nucleation and growth to be determined. Ex-situ SAXS studies provide complementary nanoscale information on the rapid self-assembly prior to MOF crystallization and in-situ powder X-ray diffraction confirms that the only crystalline phase present during the reaction is phase-pure MFM-500(Ni).