@article{long_śliwińska-bartkowiak_drozdowski_kempiński_phillips_palmer_gubbins_2013, title={High pressure effect in nanoporous carbon materials: Effects of pore geometry}, volume={437}, ISSN={0927-7757}, url={http://dx.doi.org/10.1016/j.colsurfa.2012.11.024}, DOI={10.1016/j.colsurfa.2012.11.024}, abstractNote={Abundant experimental evidence suggests that adsorbates confined in nanoporous materials exhibit high pressures, such as high pressure crystal structures, high pressure chemical reactions, and the deformation of pore walls due to the adsorbate. We report molecular simulation studies of the pressure tensor for simple adsorbates (e.g. argon) in carbon nanopores of slit, cylindrical and spherical geometries. We find that for modest bulk phase pressures of 1 bar or less, the pressures parallel to the pore walls (tangential pressure) is of the order 104–105 bar, while the pressure normal to the wall is of the order of 103 bar, and can be positive or negative depending on the pore size. Moreover, we find that the pore geometry has a large effect on the structure of the adsorbate and thus on the in-pore pressure because of the curvature that determines the strength of the adsorbate–wall interaction. For the same pore size, temperature and bulk pressure, the in-pore tangential pressure is the largest in spherical pores, followed by that in cylindrical pores and slit pores. We also study the normal pressure of carbon tetrachloride and water confined in activated carbon fibers by molecular simulations and experiments. The pressure acting on the pore wall is found to be of the order of several thousand bar by both methods. Experiments also find that the pore can be expanded or contracted, depending on pore width, as we predict by molecular simulation.}, journal={Colloids and Surfaces A: Physicochemical and Engineering Aspects}, publisher={Elsevier BV}, author={Long, Yun and Śliwińska-Bartkowiak, Małgorzata and Drozdowski, Henryk and Kempiński, Mateusz and Phillips, Katherine A. and Palmer, Jeremy C. and Gubbins, Keith E.}, year={2013}, month={Nov}, pages={33–41} }
 @article{phillips_palmer_gubbins_2012, title={Analysis of the solvation structure of rubidium bromide under nanoconfinement}, volume={38}, ISSN={["1029-0435"]}, DOI={10.1080/08927022.2012.713484}, abstractNote={We report results from a molecular simulation study of aqueous rubidium bromide solutions confined in slit-shaped carbon pores 6.5–16 Å in width, which encompasses the range typically found in nanoporous carbon electrode materials. For each slit-pore model, the structure of the solvation shells surrounding the Rb+ and Br− ions in 0.1, 0.5 and 1.0 M solutions was examined using the ion–water radial distribution functions. The impact of pore geometry on solvation structure of ions was also investigated using a disordered carbon model that morphologically resembles real nanoporous carbon electrodes. Monte Carlo simulations were used to determine the propensity of ions to reside in pores of specific sizes in the model carbon, allowing the solvation structure of Rb+ and Br− ions to be analysed as a function of pore size. We find that a dramatic drop in the solvation number occurs in pore sizes below 10 Å for slit-shaped pores, while more complex geometries see a steady decrease in solvation number as pore size is decreased. Our results suggest that, when compared to the disordered carbon model, the slit-pore model may not provide qualitatively accurate predictions regarding the structural properties of electrolytes confined in complex electrode materials.}, number={14-15}, journal={MOLECULAR SIMULATION}, author={Phillips, Katherine A. and Palmer, Jeremy C. and Gubbins, Keith E.}, year={2012}, pages={1209–1220} }