Efficient MOF-Catalyzed Ortho-Para Hydrogen Conversion for Practical Liquefaction and Energy Storage

Parahydrogen, being one of two nuclear spin isomers of molecular hydrogen, is required in a number of applications, including hydrogen liquefaction for energy storage and transportation. Obtaining pure parahydrogen is vital for these tasks, thus requiring approaches for efficient ortho-para (OP) hydrogen conversion. In this work, we for the first time demonstrate the extraordinary potential of metal-organic frameworks (MOF) as OP-conversion catalysts. In particular, the specific conversion rate constant of Ni-MOF-74 is found 145-fold higher than that of industrially used catalysts (e.g., hydrous ferric oxide), thus opening new horizons in hydrogen liquefaction and storage and, ultimately, in the broad use of hydrogen energy.