Exploiting in situ NMR to monitor the formation of a metal–organic framework

Research output: Contribution to journalArticlepeer-review

Authors

  • Corey L Jones
  • Colan E. Hughes
  • Alison Paul
  • Kenneth D. M. Harris
  • Timothy L. Easun

Colleges, School and Institutes

Abstract

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 fixed temperatures (between 60 and 100 °C) afford qualitative information on the solution-phase processes and quantitative information on the kinetics of crystallization, allowing the activation energies for nucleation (61.4 ± 9.7 kJ mol−1) and growth (72.9 ± 8.6 kJ mol−1) to be determined. Ex situ small-angle X-ray scattering studies (at 80 °C) 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 (at 90 °C) is phase-pure MFM-500(Ni). This work demonstrates that in situ NMR experiments can shed new light on MOF synthesis, opening up the technique to provide better understanding of how MOFs are formed.

Details

Original languageEnglish
Pages (from-to)1486-1494
Number of pages9
JournalChemical Science
Volume12
Issue number4
Early online date20 Nov 2020
Publication statusPublished - 28 Jan 2021