The only technologically viable method to store hydrogen is to liquefy it, as hydrogen requires impractical cryogenic temperatures for liquefaction. One major alternative is to store hydrogen within metal-organic framework materials (MOFs). One of the first of these materials to be studied for hydrogen storage is MOF-5, which is built around zinc ions and benzodicarboxylate ions. Now, a group led at American University has made a major technological leap in the processing of these materials by three-dimensionally (3D) printing a composite of acrylonitrile butadiene styrene (ABS) and MOF-5.
The group produced a range of composites with MOF mass percentages ranging from 1% to 10%. Larger amounts of MOF led to clumping and undesirable phase separation.
The MOF-5 was found to have undergone degradation due to humidity even before its incorporation into the composite, which may have led to a lowering of its hydrogen capacity. Thus, the results are expected to improve with phase pure MOF-5.
Others in the MOF community have responded positively to this work.