Figure 1. Schematic diagram of a SLIT pore (a) and a modified randomly etched graphite model (b).
Figure 2. A sketch of the LJ and TraPPE models for argon (a), nitrogen (b) and oxygen (c).
Figure 3. Singlet distribution for the nitrogen models in three slit-shaped pores (H = 8 (a), 10 (b) and 15 Å (c)) at 273.15 K and 1 bar. Filled circle symbols: 2 LJ site and square symbols: 1 LJ site.
Figure 4. Schematic diagram of nitrogen molecules adsorbed on graphite wall with slit-shaped pore (H: physical width, w or w': reentrant width, H': accessible width).
Figure 5. Calculated cumulative and pore size distribution of the slit-shaped pore and REG models. Dashed lines are cumulative distributions.
Figure 6. Molecule density of nitrogen, oxygen and argon according to physical width of slit pores, and snapshots of oxygen at 77 K and 1 bar. The solid line-segments are drawn between the individual oxygen atoms in snapshots.
Figure 7. Calculated adsorption isotherms for nitrogen in slit pores. open symbols represent desorption.
Figure 8. Adsorption isotherms on slit pore and REG models at 298 K: red, nitrogen; blue, oxygen; black, argon; filled circle, slit_H101; open rectangle, REG_A10; open triangle, REG_A20.
Figure 9. Illustration of the accessible pores in REG pore model.
Figure 10. Plot of adsorption ratio of oxygen to nitrogen as a function of pressure.
Table 1. Lennard-Jones parameters used in this work
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