Chemical Society: Dr. Michael Zaworotko

That composition and structure profoundly impact the properties of crystalline solids has provided impetus for exponential growth in the field of crystal engineering1 over the past 25 years. This lecture will address how crystal engineering has evolved from structure design (form) to control over bulk properties (function) with particular emphasis upon underexplored classes of porous material.

Whereas porous crystalline materials such as purely inorganic materials (e.g. zeolites) and those based upon coordination chemistry (e.g. Metal-Organic Frameworks, MOFs, and Porous Coordination Polymers, PCPs) are well studied and offer great promise for separations and catalysis, they are handicapped by cost or performance (e.g. poor chemical stability, interference from water vapour, low selectivity) limitations.

Hybrid Ultramicroporous Materials, HUMs, are built from metal or metal cluster “nodes” and combinations of organic and inorganic “linkers” and their pore chemistry and size (<0.7 nm) can overcome the weaknesses of existing classes of porous  material. Three prototypal families of HUMs that are amenable to fine-tuning will be detailed: (i) Pillared square grids with pcu topology can afford exceptional control over pore chemistry, pore size and binding energy for CO2.2 (ii) mmo nets are based upon square grids linked by angular inorganic linkers such as chromate anions.3 They also offer exceptional performance with respect to capture of CO2 and other polarizable gases. (iii) Diamondoid (dia) nets are long known in the field4 but little studied with respect to gas adsorption. New results concerning the structure and gas sorption properties of pcu, mmo and dia nets will be presented. In particular, their performance with respect to direct carbon capture from air (Figure) and natural gas storage will be presented and discussed in the context of existing classes of porous materials.

References

1. (a) Desiraju, G.R. Crystal engineering: The design of organic solids Elsevier, 1989; (b) Moulton, B.; Zaworotko, M.J. Chem. Rev.  2001, 101, 1629.

2. Nugent, P.; Belmabkhout, Y.; Burd, S.D.; Cairns, A.J.; Luebke, R.; Forrest, K.; Pham, T.; Ma, S.; Space, B.; Wojtas, L.; Eddaoudi, M.; Zaworotko, M.J. Nature 2013, 495, 80.

3. Mohamed, M.; Elsaidi, S.; Wojtas, L.; Pham, T.; Forrest, K.A.; Tudor, B.; Space, B.; Zaworotko, M.J. J.

Amer. Chem. Soc. 2012, 134, 19556.

4. Zaworotko, M.J. Chem. Soc. Rev. 1994, 23, 283.

5. Kumar, A.; Madden, D.G.; Lusi, M.; Chen, K.J.; Daniels, E.A.; Curtin, T.; Perry IV, J.J.; Zaworotko, M.J.

Angew. Chem. Int. Ed. (accepted for publication September 4th 2015)