Adsorption in micro and mesoporous slit carbons with oxygen surface functionalities

Gotzias, Anastasios; Tylianakis, Emmanuel; Froudakis, Georgios; Steriotis, Theodore

doi:10.1016/j.micromeso.2014.08.052

Cited by 17 publications

(7 citation statements)

References 63 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In our earlier work we adapted a similar strategy to demonstrate exclusively the N doping effect on CO 2 uptake, and additionally such assumptions also successfully predicted the experimentally observed isosteric heat values and the theoretical limit of N doped carbons . Such approach was also earlier used by other researchers to estimate the H 2 uptake in oxygenated carbon surfaces, single and binary adsorption of CO 2 and CH 4 and their mixtures in oxygenated carbons, and water adsorption in oxygenated surfaces, and to obtain the kinetic and thermodynamic selectivity of CO 2 /CH 4 of carbon materials. − …”

Section: Simulation Detailsmentioning

confidence: 80%

Understanding the Hydrophilicity and Water Adsorption Behavior of Nanoporous Nitrogen-Doped Carbons

et al. 2016

View full text Add to dashboard Cite

Through molecular simulation we exposed the anomalous water adsorption behavior in slit-shaped and disordered nitrogen doped carbons. Instead of Langmuirian, water adsorption proceeds via mechanisms analogous to crystal nucleation: birth and spread of (poly) nucleation sites in one, two, and three dimensions forming water nanowires/pillars and water clusters before complete pore filling via capillary condensation. The adsorption of water and the adsorption hysteresis in N-doped carbons are strongly influenced by the poresize. The smaller the pore-size, the smaller is the pressure at which the abovementioned process tends to occur in N-doped carbons. The nucleation analogues are clearly visible in a pore that has a homogeneous pore structure, whereas in disordered pore structures, the complex and distributed pore-sizes disturb these nucleation analogue patterns especially at lower relative pressures. The effect of the adsorbed water molecules on the connectivity of the available pore volume is discussed. Adsorption at zero loading confirmed water molecules preferentially adsorb over specific zones, which corresponds to regions with a high local density of N atoms rather than specific sites or type of N (such as graphitic or pyridinic). Simulated adsorption isotherms showed the hydrophilicity introduced to the carbon pore via N doping is sensitive to impurities such as water, such that it can affect the ability of the carbon framework to host another guest molecule such as CO 2 , a prime fluid involved in flue gas.

show abstract

Section: Simulation Detailsmentioning

confidence: 80%

Understanding the Hydrophilicity and Water Adsorption Behavior of Nanoporous Nitrogen-Doped Carbons

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Molecular simulations also showed that fractional layers of gas molecules (for example 1.5, 2.5 and 3.5 layers) in the pores tend to pack in a more disordered manner as the molecule adsorbed on one side of pore effect the adsorption on other side of the pore-wall. Gotzias et al 101 performed molecular simulations to study the adsorption of Ar at 87 K in pristine and oxygen functionalized carbons. It was found that the isosteric heat due to solid-fluid interactions decreased with surface coverage whereas the isosteric heat due to fluidfluid interactions progressively increased, especially at higher loadings.…”

Section: Isosteric Heatmentioning

confidence: 99%

Characterization of the adsorption site energies and heterogeneous surfaces of porous materials

et al. 2019

View full text Add to dashboard Cite

show abstract

“…These groups are anchored on a graphitic surface and then we form the slit-shaped pore models. [53][54][55] As seen in Figure 1, the wetted layers of the slit pore along with the functional groups are defined atomistically. Solid-fluid interactions are expressed by a summation over all pair-wised LJ and electrostatic interactions that stem from that layer at both sides of the pore.…”

Section: Simulation Algorithm and Potential Modelmentioning

confidence: 99%

“…an oxygen-free graphitic surface) is also considered for comparison. Structural optimisations and computations of partial charges were conducted with the turbomole software at the DFT level of theory as described in [55]. The interaction parameters of the atoms on the solid are listed in Table 2 while the partial charges assigned for the different surface models are listed in Table 3.…”

Section: Simulation Algorithm and Potential Modelmentioning

confidence: 99%

On the orientation of N₂and CO₂molecules adsorbed in slit pore models with oxidised graphitic surface

Gotzias

Charalambopoulou

Steriotis

2015

Molecular Simulation

View full text Add to dashboard Cite

We report grand canonical Monte Carlo studies of nitrogen (77 K) and carbon dioxide (253 K) adsorbed in graphitic slit pores with surface oxygen functionalities. The analysis is focused on the molecular orientation within the adsorption layers and the influence of surface heterogeneity on molecular density distributions. The oxygen-containing surface functionalities act like additional adsorption sites along the graphitic basal plane that interacts also electrostatically with the fluid. Our simulations reveal that the molecular orientation of both adsorbate particles changes greatly upon increasing surface heterogeneity, while the effect of the pore size on the adsorption behaviour is also discussed. The detailed microscopic description of the adsorbed layer on oxygen modified carbon surfaces can be used to highlight thermodynamic features of gas adsorption on real surfaces such as layering transitions and surface area calculations.

show abstract

Adsorption in micro and mesoporous slit carbons with oxygen surface functionalities

Cited by 17 publications

References 63 publications

Understanding the Hydrophilicity and Water Adsorption Behavior of Nanoporous Nitrogen-Doped Carbons

Understanding the Hydrophilicity and Water Adsorption Behavior of Nanoporous Nitrogen-Doped Carbons

Characterization of the adsorption site energies and heterogeneous surfaces of porous materials

On the orientation of N₂and CO₂molecules adsorbed in slit pore models with oxidised graphitic surface

Contact Info

Product

Resources

About

Adsorption in micro and mesoporous slit carbons with oxygen surface functionalities

Cited by 17 publications

References 63 publications

Understanding the Hydrophilicity and Water Adsorption Behavior of Nanoporous Nitrogen-Doped Carbons

Understanding the Hydrophilicity and Water Adsorption Behavior of Nanoporous Nitrogen-Doped Carbons

Characterization of the adsorption site energies and heterogeneous surfaces of porous materials

On the orientation of N2and CO2molecules adsorbed in slit pore models with oxidised graphitic surface

Contact Info

Product

Resources

About

On the orientation of N₂and CO₂molecules adsorbed in slit pore models with oxidised graphitic surface