Krekelberg William P, Siderius Daniel W, Shen Vincent K, Truskett Thomas M, Errington Jeffrey R
Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, USA.
McKetta Department of Chemical Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
J Phys Chem C Nanomater Interfaces. 2017 Aug 3;121(30):16316-16327. doi: 10.1021/acs.jpcc.7b04232. Epub 2017 Jul 5.
Using molecular simulations, we investigate how the range of fluid-fluid (adsorbate-adsorbate) interactions and the strength of fluid-solid (adsorbate-adsorbent) interactions impact the strong connection between distinct adsorptive regimes and distinct self-diffusivity regimes reported in [Krekelberg, W. P.; Siderius, D. W.; Shen, V. K.; Truskett, T. M.; Errington, J. R. , , 14527-14535]. Although increasing the fluid-fluid interaction range changes both the thermodynamics and the dynamic properties of adsorbed fluids, the previously reported connection between adsorptive filling regimes and self-diffusivity regimes remains. Increasing the fluid-fluid interaction range leads to enhanced layering and decreased self-diffusivity in the multilayer-formation regime but has little effect on the properties within film-formation and pore-filling regimes. We also find that weakly attractive adsorbents, which do not display distinct multilayer formation, are hard-sphere-like at super- and subcritical temperatures. In this case, the self-diffusivity of the confined and bulk fluid has a nearly identical scaling-relationship with effective density.
通过分子模拟，我们研究了流体 - 流体（吸附质 - 吸附质）相互作用范围以及流体 - 固体（吸附质 - 吸附剂）相互作用强度如何影响[Krekelberg, W. P.; Siderius, D. W.; Shen, V. K.; Truskett, T. M.; Errington, J. R.,, 14527 - 14535]中报道的不同吸附状态与不同自扩散状态之间的紧密联系。尽管增加流体 - 流体相互作用范围会改变吸附流体的热力学和动力学性质，但先前报道的吸附填充状态与自扩散状态之间的联系仍然存在。增加流体 - 流体相互作用范围会导致多层形成状态下的分层增强和自扩散降低，但对成膜和孔填充状态下的性质影响很小。我们还发现，不显示明显多层形成的弱吸引性吸附剂在超临界和亚临界温度下类似硬球。在这种情况下，受限流体和本体流体的自扩散与有效密度具有几乎相同的标度关系。
