Article Review · Nature · 2004

MOF-177 and the Surface Area Arms Race

PaperA route to high surface area, porosity and inclusion of large molecules in crystals
AuthorsH. K. Chae, D. Y. Siberio-Perez, J. Kim, Y. Go, M. Eddaoudi, A. J. Matzger, M. O'Keeffe, O. M. Yaghi
PublishedNature, 2004
DOI10.1038/nature02311
Read the Original Paper ↗

By 2004 the obvious route to bigger pores, longer linear linkers, kept failing: frameworks either collapsed or grew a second interpenetrating copy of themselves inside their own cavities. MOF-177's contribution was geometric. Chae and colleagues paired the trusty Zn4O cluster with a large triangular linker, BTB, whose three-fold symmetry is incompatible with self-interpenetration in the resulting qom net. The frustration was deliberate, and it worked.

The measured Langmuir surface area of about 4,500 m2/g crushed every prior porous material, crystalline or amorphous. More vivid than the number was the demonstration: the crystals soaked up bulky polycyclic dyes such as Astrazon Orange, molecules far too large for any zeolite, proving the pores were not just statistically large but usable by real cargo. That single experiment previewed the entire later field of MOF-based drug loading and enzyme encapsulation.

Points of critique are modest but real. Like its zinc-carboxylate relatives, MOF-177 hydrolyzes in humid air, so the record material was never a practical one. The dye-inclusion experiments are qualitative, beautiful photographs rather than quantified loading isotherms. And the paper marks the start of a surface-area arms race that consumed considerable community effort on materials whose fragility limited them to bragging rights, a pattern later record-holders repeated.

Still, the design lesson, use linker symmetry to forbid interpenetration rather than fighting it empirically, entered the standard toolbox immediately, and MOF-177 itself became the field's cryogenic hydrogen benchmark for years. This is what a good record paper looks like: the number gets the headline, the geometry gets the citations.

Reviewer's VerdictA record paper with a real idea underneath: triangular linkers frustrate interpenetration.

This review reflects the independent opinion of Team LR at MOFsResearch.com. It is an educational commentary on the cited publication and is not affiliated with or endorsed by the original authors or publisher. Verify all figures against the original paper before use.