Liquids with permanent porosity
Top Cited Papers
- 11 November 2015
- journal article
- letter
- Published by Springer Science and Business Media LLC in Nature
- Vol. 527 (7577), 216-220
- https://doi.org/10.1038/nature16072
Abstract
Porous solids such as zeolites1 and metal–organic frameworks2,3 are useful in molecular separation and in catalysis, but their solid nature can impose limitations. For example, liquid solvents, rather than porous solids, are the most mature technology for post-combustion capture of carbon dioxide because liquid circulation systems are more easily retrofitted to existing plants. Solid porous adsorbents offer major benefits, such as lower energy penalties in adsorption–desorption cycles4, but they are difficult to implement in conventional flow processes. Materials that combine the properties of fluidity and permanent porosity could therefore offer technological advantages, but permanent porosity is not associated with conventional liquids5. Here we report free-flowing liquids whose bulk properties are determined by their permanent porosity. To achieve this, we designed cage molecules6,7 that provide a well-defined pore space and that are highly soluble in solvents whose molecules are too large to enter the pores. The concentration of unoccupied cages can thus be around 500 times greater than in other molecular solutions that contain cavities8,9,10, resulting in a marked change in bulk properties, such as an eightfold increase in the solubility of methane gas. Our results provide the basis for development of a new class of functional porous materials for chemical processes, and we present a one-step, multigram scale-up route for highly soluble ‘scrambled’ porous cages prepared from a mixture of commercially available reagents. The unifying design principle for these materials is the avoidance of functional groups that can penetrate into the molecular cage cavities.Keywords
This publication has 33 references indexed in Scilit:
- Porous organic molecular solids by dynamic covalent scramblingNature Communications, 2011
- Free Volume of Interphases in Model Nanocomposites Studied by Positron Annihilation Lifetime SpectroscopyMacromolecules, 2010
- Encapsulation of Small Gas Molecules by Cryptophane-111 in Organic Solution. 1. Size- and Shape-Selective Complexation of Simple HydrocarbonsThe Journal of Physical Chemistry A, 2009
- GROMACS 4: Algorithms for Highly Efficient, Load-Balanced, and Scalable Molecular SimulationJournal of Chemical Theory and Computation, 2008
- Porous LiquidsChemistry – A European Journal, 2007
- Solubility of carbon dioxide, ethane, methane, oxygen, nitrogen, hydrogen, argon, and carbon monoxide in 1-butyl-3-methylimidazolium tetrafluoroborate between temperatures 283K and 343K and at pressures close to atmosphericThe Journal of Chemical Thermodynamics, 2006
- The calculation of the potential of mean force using computer simulationsComputer Physics Communications, 1995
- Solubility of Methane in Benzene, Naphthalene, Phenanthrene, and Pyrene at Temperatures from 323 to 433 K and Pressures to 11.3 MPaJournal of Chemical & Engineering Data, 1994
- Host-guest complexation. 67. A highly adaptive and strongly binding hemicarcerandJournal of the American Chemical Society, 1994
- THE weighted histogram analysis method for free‐energy calculations on biomolecules. I. The methodJournal of Computational Chemistry, 1992