(452d) High-Throughput Screening of Metal-Organic Frameworks for Hydrogen Storage

Authors: 
Bobbitt, N. S., Northwestern University
Snurr, R. Q., Northwestern University
Chen, J., Northwestern University
Metal-organic frameworks (MOFs) are porous materials consisting of metal nodes connected with organic linkers. This class of materials has high surface area and porosity, which make them attractive candidates for gas adsorption applications. Because MOFs can be made from a vast array of nodes, organic linkers, and functional groups, there are a huge number of possible MOF structures. High-throughput computational screening can efficiently characterize large numbers of materials to identify the best candidates for adsorption. [1,2]

In this study, we screened over 130,000 candidate structures [3] for hydrogen storage capacity at cryogenic conditions (77 K), considering loading at 100 bar and desorption at 2 bar using grand canonical Monte Carlo simulations. We also calculated textual properties such as surface area, pore diameter, and void fraction and examined adsorption performance trends with respect to these properties.

Several thousand of the structures exceed the DOE gravimetric adsorption target of 7.5 weight percent; however, none of them meet the volumetric target of 70 g/L. The highest volumetric adsorption we find in this database is 50 g/L.

We will discuss structure-performance trends as well as common traits in the best-performing groups of MOFs. We will also introduce a fast, computationally efficient method of screening MOF structures for gas adsorption performance based on geometry and pore size.

References:

1. Y.J. Colon, R.Q. Snurr, â??High-throughput computational screening of metal-organic frameworks,â?Â Chem. Soc. Rev. 43, 5735-5749 (2014).

2. H. Frost, R.Q. Snurr, "Design requirements for metal-organic frameworks as hydrogen storage materials," J. Phys. Chem. C 111 18794-18803 (2007).

3. C.E. Wilmer, M. Leaf, C.Y. Lee, O.K. Farha, B.G. Hauser, J.T. Hupp, R.Q. Snurr, "Large-scale screening of hypothetical metal-organic frameworks," Nature Chem., 4, 83-89 (2012)