Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations
Adsorption and separation properties of gyroidal nanoporous carbons (GNCs) - a new class of exotic nanocarbon materials are studied for the first time using hyper parallel tempering Monte Carlo Simulation technique. Porous structure of GNC models is evaluated by the method proposed by Bhattacharya a...
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Інститут фізики конденсованих систем НАН України
2016
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irk-123456789-1557902019-06-18T01:29:52Z Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations Furmaniak, S. Gauden, P.A. Terzyk, A.P. Kowalczyk, P. Adsorption and separation properties of gyroidal nanoporous carbons (GNCs) - a new class of exotic nanocarbon materials are studied for the first time using hyper parallel tempering Monte Carlo Simulation technique. Porous structure of GNC models is evaluated by the method proposed by Bhattacharya and Gubbins. All the studied structures are strictly microporous. Next, mechanisms of Ar adsorption are described basing on the analysis of adsorption isotherms, enthalpy plots, the values of Henry’s constants, αs and adsorption potential distribution plots. It is concluded that below pore diameters ca. 0.8 nm, primary micropore filling process dominates. For structures possessing larger micropores, primary and secondary micropore filling mechanism is observed. Finally, the separation properties of GNC toward CO₂/CH₄, CO₂/N₂, and CH₄/N₂ mixtures are discussed and compared with separation properties of Virtual Porous Carbon models. GNCs may be considered as potential adsorbents for gas mixture separation, having separation efficiency similar or even higher than activated carbons with similar diameters of pores. Адсорбцiя i особливостi роздiлення у гiроїдних нанопористих вуглецях (GNC), новому класi екзотичних нановуглецевих матерiалiв, вперше дослiджено, використовуючи метод моделювання Монте Карло з гiперпаралельним темперуванням. Пориста структура GNC моделей оцiнюється методом, запропонованим Бхатачарiя i Губiнсом. Всi дослiдженi структури є строго мiкропористi. Крiм того, механiзми адсорбцiї Ar описуються на основi аналiзу iзотерм адсорбцiї, кривих ентальпiї, значень сталих Генрi, αs та кривих розподiлу потенцiалу адсорбцiї. Зроблено висновок, що при дiаметрах пор близьких або менших за 0.8 nm домiнує процес заповнення первинних мiкропор. Для структур, що мають бiльшi мiкропори, спостерiгається механiзм заповнення первинних та вторинних мiкропор. Нарештi, описано властивостi роздiлення CO₂/CH₄, CO₂/N₂, і CH₄/N₂ сумiшей у GNC i виконано порiвняння з властивостями роздiлення моделей Вiртуального Пористого Вуглецю. Гiроїднi пористi вуглецi можна розглядати як потенцiйнi адсорбенти для роздiлення газових сумiшей, якi володiють аналогiчною або навiть вищою ефективнiстю роздiлення, нiж активований вуглець з подiбним дiаметром пор. 2016 Article Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations / S. Furmaniak, P.A. Gauden, A.P. Terzyk, P. Kowalczyk // Condensed Matter Physics. — 2016. — Т. 19, № 1. — С. 13003: 1–14. — Бібліогр.: 98 назв. — англ. 1607-324X DOI:10.5488/CMP.19.13003 arXiv:1603.02161 PACS: 05.10.Ln, 05.70.-a, 51.10.+y, 51.30.+i, 64.75.+g http://dspace.nbuv.gov.ua/handle/123456789/155790 en Condensed Matter Physics Інститут фізики конденсованих систем НАН України |
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Adsorption and separation properties of gyroidal nanoporous carbons (GNCs) - a new class of exotic nanocarbon materials are studied for the first time using hyper parallel tempering Monte Carlo Simulation technique. Porous structure of GNC models is evaluated by the method proposed by Bhattacharya and Gubbins. All the studied structures are strictly microporous. Next, mechanisms of Ar adsorption are described basing on the analysis of adsorption isotherms, enthalpy plots, the values of Henry’s constants, αs and adsorption potential distribution plots. It is concluded that below pore diameters ca. 0.8 nm, primary micropore filling process dominates. For structures possessing larger micropores, primary and secondary micropore filling mechanism is observed. Finally, the separation properties of GNC toward CO₂/CH₄, CO₂/N₂, and CH₄/N₂ mixtures are discussed and compared with separation properties of Virtual Porous Carbon models. GNCs may be considered as potential adsorbents for gas mixture separation, having separation efficiency similar or even higher than activated carbons with similar diameters of pores. |
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Furmaniak, S. Gauden, P.A. Terzyk, A.P. Kowalczyk, P. |
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Furmaniak, S. Gauden, P.A. Terzyk, A.P. Kowalczyk, P. Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations Condensed Matter Physics |
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Furmaniak, S. Gauden, P.A. Terzyk, A.P. Kowalczyk, P. |
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Furmaniak, S. |
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Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations |
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Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations |
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Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations |
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Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations |
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Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations |
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gyroidal nanoporous carbons - adsorption and separation properties explored using computer simulations |
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Інститут фізики конденсованих систем НАН України |
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2016 |
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Gyroidal nanoporous carbons - Adsorption and separation properties explored using computer simulations / S. Furmaniak, P.A. Gauden, A.P. Terzyk, P. Kowalczyk // Condensed Matter Physics. — 2016. — Т. 19, № 1. — С. 13003: 1–14. — Бібліогр.: 98 назв. — англ. |
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Condensed Matter Physics |
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2025-07-14T08:01:34Z |
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| fulltext |
Condensed Matter Physics, 2016, Vol. 19, No 1, 13003: 1–14
DOI: 10.5488/CMP.19.13003
http://www.icmp.lviv.ua/journal
Gyroidal nanoporous carbons— Adsorption and
separation properties explored using
computer simulations
∗
S. Furmaniak1, P.A. Gauden1, A.P. Terzyk1, P. Kowalczyk2
1 Faculty of Chemistry, Physicochemistry of Carbon Materials Research Group,
Nicolaus Copernicus University in Toruń, Gagarin St. 7, 87–100 Toruń, Poland
2 School of Engineering and Information Technology, Murdoch University,
Murdoch, Western Australia 6150, Australia
Received November 13, 2015, in final form December 17, 2015
Adsorption and separation properties of gyroidal nanoporous carbons (GNCs)— a new class of exotic nanocar-
bon materials are studied for the first time using hyper parallel tempering Monte Carlo Simulation technique.
Porous structure of GNC models is evaluated by the method proposed by Bhattacharya and Gubbins. All the
studied structures are strictly microporous. Next, mechanisms of Ar adsorption are described basing on the
analysis of adsorption isotherms, enthalpy plots, the values of Henry’s constants, αs and adsorption poten-tial distribution plots. It is concluded that below pore diameters ca. 0.8 nm, primary micropore filling process
dominates. For structures possessing larger micropores, primary and secondary micropore filling mechanism
is observed. Finally, the separation properties of GNC toward CO2/CH4, CO2/N2, and CH4/N2 mixtures are dis-cussed and compared with separation properties of Virtual Porous Carbon models. GNCs may be considered
as potential adsorbents for gas mixture separation, having separation efficiency similar or even higher than
activated carbons with similar diameters of pores.
Key words: gyroidal nanoporous carbons, adsorption, gas mixtures separation, Monte Carlo simulations
PACS: 05.10.Ln, 05.70.-a, 51.10.+y, 51.30.+i, 64.75.+g
1. Introduction
Adsorption of gas mixtures on solid surfaces has been attracting great interest for many years [1–7].
In the last decades there has been observed an increased interest to the development of new separation
and purification techniques. It is evident that adsorption using various adsorbents is still a versatile tool
for these purposes. On the other hand, the basic problem appearing in experimental studies is caused
by difficulties in the synthesis of nanomaterials possessing desired properties. It is still not simple to
control porosity and/or the chemical nature of the surface, and the both parameters at the same time.
Moreover, experimental data on mixed systems are very limited, i.e., in the case of mixtures consisting
of two volatile components the problem of the surface coverage determination has not been fully solved
yet. Predicting adsorption behaviour of mixtures from pure component data is very important, from both
the theoretical and practical viewpoints [8–14]. It is well known that the theoretical calculations provide
additional opportunities for studies to better understand the separation processes. However, despite the
intensive experimental and theoretical studies, our knowledge of the properties and the structure of
mixed adsorbed layers is rather sparse, especially, on new generations of nanoporous adsorbents.
Computer simulation is an efficient method for resolving the above mentioned problems, since it is
capable of modelling the processes of interest at the required level of detail in a controllable environ-
ment, providing the necessary tools for establishing the connections between the observed phenomena
∗This paper is dedicated to Prof. Stefan Sokołowski on the occasion of his 65th birthday.
© S. Furmaniak, P.A. Gauden, A.P. Terzyk, P. Kowalczyk, 2016 13003-1
http://dx.doi.org/10.5488/CMP.19.13003
http://www.icmp.lviv.ua/journal
S. Furmaniak et al.
and their molecular-level physical background. Prof. Sokołowski’s (and co-workers) research topics of
interest have also been concerned with the issue of mixtures using Monte Carlo simulations [15–22], Den-
sity Functional Theory [23–28], and Dissipative Particle Dynamics [29]. Their inspiring articles discuss,
for example, the following problems: (i) adsorption from mixtures of monomers [15], dimers [15], the
chain molecules [30, 31], and even polymer mixtures [27], (ii) adsorption frommixtures on homogeneous
[25, 32] and heterogeneous surfaces [15, 33, 34], (iii) layering transition, capillary condensation, wetting
phenomena, and multilayer adsorption of binary ideal mixtures, systems exhibiting negative deviations
from ideal mixing or positive one, binary mixture with partially miscible components, etc. [16, 17, 34–
38], (iv) interaction of charged chain particles and spherical counterions in contact with charged hard
wall [31], (v) analysis of the properties of two-dimensional symmetrical mixtures in an external field of
square symmetry [39, 40], (vi) demixing and freezing in two-dimensional symmetrical mixtures [21], and
(vii) the behaviour of mixed two component submonolayer films (Ar and Kr [41, 42] or Kr and Xe [22]
on graphite). The majority of the analysed adsorbents have an ideal geometry of pores, for example a
slit-like [25, 26, 32, 34, 43]. However, more complex models have also been studied, for example, pillared
slit-like pores [28] and slit-like pores with walls decorated by tethered polymer brushes in the form of
stripes [29].
In the last decades, novel exotic porous carbon nanostructures (such as carbon nanotubes (CNTs),
single-walled carbon nanohorns, graphene and graphitic nanoribbons, ordered porous carbons, worm-
like nanotubes and graphitic nanofibers, stacked-cup carbon nanofibers, cubic carbon allotropes, carbon
onions, carbyne networks, and others) have been projected to be among the most useful materials for
selective adsorption and separation of fluid mixtures [44–48]. However, in the theoretical studies, differ-
ent carbon adsorbents are studied, such as: carbon nanotubes [13, 49–53], carbon nanohorns [13, 51, 54],
2D and 3D ordered carbon networks [55], hydrophobic virtual porous carbons (VPCs) [12, 14, 56–62], ox-
idized VPCs [12, 14, 60, 62, 63], and triply periodic carbon minimal surfaces (Schwarz’s primitive and
Schoen’s gyroid) [45, 59, 64–70]. Recently, scientists have paid attention to the next generation of porous
carbon molecular sieves materials, i.e., crystalline exotic cubic carbon allotropes: cubic carbon poly-
morphs (CCPs) [45, 71–73], diamond-like super structures of CNTs (super diamonds) [74], diamond-like
frameworks [75], porous aromatic frameworks (PAFs) [76, 77], diamond-like carbon frameworks (i.e., di-
amondynes, also named D-carbons) [78], tetrahedral node diamondyne [79], carbon allotropes proposed
by Karfunkel and Dressler [45, 80], compressed carbon nanotubes [45, 81], sodalite-like nanostructures
[45, 82], folding of graphene slit-like pore walls [52, 83], gyroidal nanoporous and mesoporous carbons
(GNCs and GMCs, respectively) [84–86].
One of themost interesting and promising adsorbent from the abovementioned is GNC. In the current
study, we consider nine different GNC structures having surface built in a way ensuring connection of
each carbon atom with exactly three neighbours, similarly as “schwarzites”. Nicolaï et al. [84] confirmed
that the curvature and the rigidity do not play a crucial role in the performance of GNC structures for
ionic conduction. The major role, however, is played by the pore size and pore volume. Indeed, the larger
the pore is, the larger is the ionic transport. Finally, the mentioned authors stated that GNC structures
with tunable properties can be widely applied to water filtration or energy storage.
2. Simulation details
We used the structures of nine gyroidal nanocarbons (denoted as GNC-04, GNC-07, GNC-09, GNC-11,
GNC-12, GNC-13, GNC-15, GNC-18 and GNC-21) published previously by Nicolaï et al. [84] (see figure 1 in
[84]). In the case of the first six systems, original boxes generated by Nicolaï et al. [84] were multiplied
(eightfold) in order to obtain box size at least two times greater than the cut-off distances used during
simulations described below. The porosity of all the studied carbonaceous adsorbents was characterised
by a geometrical method proposed by Bhattacharya and Gubbins (BG) [87]. The implementation of the
method was described in detail elsewhere [88, 89]. The BG method provided histograms of pore sizes
(effective diameters— deff). These data were also used to calculate the average sizes of pores accessiblefor Ar atoms (deff,acc,av) [88]. In addition, the volume of pores accessible for Ar was determined using acombination of the BG method and Monte Carlo integration [88].
Argon adsorption isotherms at its boiling point (i.e., T = 87 K) on all the studied nanocarbons were
13003-2
Gyroidal nanoporous carbons— Adsorption and separation properties
simulated using the hyper parallel tempering Monte Carlo method (HPTMC) proposed by Yan and de
Pablo [90]. The simulation scheme was the same as in previous work [88]. We considered 93 replicas
corresponding to different relative pressure values (p/ps, where p and ps are equilibrium and saturatedAr vapour pressure, respectively) in the range 1.0×10−10 −1.0. Other details of the performed HPTMC
simulations are described in [88]. The average numbers of Ar atoms in the simulation box were used to
calculate the adsorption amount of Ar per unit of mass of the adsorbent (a) [88]. The isosteric enthalpy
of adsorption (qst) was also determined from the theory of fluctuations [88, 91] to reflect the energetics
of the process.
In order to analyse the mechanism of Ar adsorption, we constructed high resolution αs-plots [92]based on simulated adsorption isotherms. We used Ar adsorption isotherm simulated in the ideal slit-
like system composed of graphene sheets with effective pore width equal to 10 nm as the reference one.
We also determined the values of Henry’s constant (KH) from the slope of the linear part of adsorptionisotherms in the low-pressure range [83]. Finally, adsorption potential distribution (APD) curves [93–95]
were calculated. The APD curve is the first derivative of the so-called characteristic curve, presenting
adsorption amount as a function of the adsorption potential (Apot) defined as:
Apot =−RT ln
p
ps , (2.1)
where R is the universal gas constant. The differentiation was performed numerically by the approxima-
tion of the isotherms using some empirical functions and calculating their derivatives.
We also simulated the adsorption and separation of three binary gas mixtures (important from prac-
tical point of view): CO2/CH4, CO2/N2, and CH4/N2 on all the studied GNCs. The computations were per-formed for T = 298 K using the grand canonical Monte Carlo method (GCMC) [91, 96]. The simulation
schemewas the same as in our previous works [60, 62]. Simulations were performed for the total mixture
pressure ptot = 0.1 MPa (i.e., atmospheric pressure) and for the following mole fractions of components
in the gaseous phase (y): 0.0, 0.01, 0.025, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95, 0.975, 0.99, and
Figure 1. (Color online) Comparison of (a) pore size histograms for all the studied nanocarbons deter-
mined from the BG method (the subsequent histograms are shifted by 1 unit from the previous ones), (b)
average sizes and (c) volume of pores accessible for Ar atoms, respectively.
13003-3
S. Furmaniak et al.
1.0. For each point, the mole fractions of components in the adsorbed phase (x) were calculated from the
average numbers of molecules present in the simulation box. The efficiency of the process of separation
of mixtures was reflected by the value of equilibrium separation factor (the 1st component over the 2nd
one):
S1/2 = x1/x2
y1/y2
. (2.2)
The adsorbed phase is enriched in the 1st component if S1/2 > 1.
3. Results and discussion
Figure 1 (a) collects histograms of effective pore sizes, determined from the application of BGmethod,
for all the studied GNCs. All the structures are strictly microporous, i.e., the diameters of pores do not
exceed 2 nm. Generally, the size of dominant pores increases in the considered series (from the GNC-
04 up to GNC-21). However, there are two groups of nanocarbons having similar diameters of the main
pores: (i) GNC-11, GNC-12 and GNC-13 — deff around 1 nm and (ii) GNC-18 and GNC-21 — deff around1.5 nm. It should be noted that in the case of GNC-21, some amount of pores wider than in GNC-18 is also
present. These regularities are reflected by the values of the average pore diameter [figure 1 (b)]. The
increase in pore diameters is accomplished by the increase in pore volume from ca. 0.4 cm3/g for GNC-04
up to ca. 1.3 cm3/g for GNC-18 and GNC-21 [figure 1 (c)].
Figure 2 shows the comparison of Ar adsorption isotherms simulated for all the studied GNCs. The
Figure 2. (Color online) Comparison of Ar adsorption isotherms (T = 87 K) simulated for all the considered
nanocarbons.
13003-4
Gyroidal nanoporous carbons— Adsorption and separation properties
Figure 3. (Color online) Equilibrium argon configurations for selected nanocarbons and selected values of
relative pressure (the frames reflect the size of simulation boxes, all the structures are in the same scale).
It should be noted that this figure was created using the VMD program [97].
changes observed in the shape of isotherms reflect the differences in the properties of nanocarbons.
Adsorption capacity varies from ca. 12 mmol/g for GNC-04 up to ca. 45 mmol/g for GNC-18 and GNC-21.
These changes correspond to the differences in the pore volume [figure 1 (c)]. At the same time, the shift
of the pore filling pressure toward higher values is observed. The pores of the GNC-04 structure are filled
in the relative pressure range 10−8 − 10−6. However, the total filling of GNC-18 and GNC-21 occurs for
similar values of relative pressure (around 10−2). The middle carbons of the series (i.e., GNC-11, GNC-12
and GNC-13) are filled in the similar range of relative pressure (p/ps > 10−4). The differences in the pore
filling are also clearly seen on equilibrium snapshots of Ar configurations in the simulation boxes shown
in figure 3. These regularities are related to the differences in diameters of dominant pores present in
the individual GNCs [figure 1 (a)]. Finally, one can observe that in the case of initial structures (up to
GNC-13), the pore filling is a single-step process. However, the pores of GNC-15, GNC-18 and GNC-21 are
filled in two steps. This is also caused by the rise in pore sizes. For pores wider than 1 nm, in the first step
13003-5
S. Furmaniak et al.
Figure 4. (Color online) Comparison of isosteric enthalpy of Ar adsorption [the data related to figure 2; for
clarity adsorption amounts are normalised by the maximum observed value (amax)].
a monolayer is formed and next the remaining free volume is filled.
Figure 4 shows the plots of isosteric enthalpy of adsorption related to the isotherms shown in figure 2.
For low loadings, the qst values increase as the adsorption amount rises. In this range, Ar atoms are ad-
sorbed mainly on high-energetic centres. The increasing adsorption amount causes other Ar atoms to
appear in the vicinity of the initially adsorbed ones. This rises the contribution of fluid-fluid interactions
to the total energy of a system. Here, the only exception is GNC-21 structure. There is observed a decrease
in qst for relative adsorption up to ca. 0.1. This system has probably got a heterogeneous surface. Con-
sequently, the subsequent Ar atoms are adsorbed on centres having lower energy and this reduces the
effects of the increase in lateral Ar-Ar interactions. In the intermediate range of adsorption, the enthalpy
rises for all the structures until the entire adsorbent surface is covered. Next, the values of qst decrease
since Ar is adsorbed at the places more distant from the surface and this is connected with lower solid-
fluid contributions. In the case of the structures having the widest pores (especially GNC-15, GNC-18 and
GNC-21), the second peak on qst is also observed. This peak is related to the total filling of pores.
Comparing the enthalpy at zero coverage for all the systems, one can observe that GNC-04 has a re-
markably higher value of this parameter (ca. 17.5 kJ/mol) than the other systems. This is connected with
the presence of the narrowest pores having high adsorption energy. The other structures may be divided
into two groups. The first one includes GNC-07, GNC-09, GNC-12, GNC-13 and GNC-21 carbons. In this case,
the enthalpy at zero coverage is close to 12 kJ/mol. For the second group (GNC-11, GNC-15 and GNC-18),
this enthalpy value is in the range 9–10 kJ/mol. This may suggest some similarities in the surface nature of
the group members (for example curvature, which is the main factor determining the energy of adsorp-
tion on the surface). The above-described differences in the energy of interactions with the surface of
13003-6
Gyroidal nanoporous carbons— Adsorption and separation properties
Figure 5. (Color online) Comparison of Henry’s constants related to the Ar adsorption isotherms presented
on figure 2.
Figure 6. (Color online) Comparison of αs-plots related to the Ar adsorption isotherms presented in fig-ure 2 [for clarity the adsorption amounts are normalized by themaximumobserved value (amax)]. Theαsis the normalized adsorption on the reference material, i.e., in the ideal slit-like system with the effective
pore width equal to 10 nm.
13003-7
S. Furmaniak et al.
Figure 7. (Color online) (a) Comparison of APD curves [for clarity, all the curves are normalized by the
maximum observed value (APDmax); subsequent curves are shifted by 1.35 units]. (b) Location of themain peak on the APD curves (Apot,max). (c) Correlation between the location of the main peak and theaverage sizes of pores accessible for Ar atoms.
adsorbents fully correspond to the variation of Henry’s constants shown in figure 5. This is not surprising
since solid-fluid interactions are the main factor affecting the shape of the isotherm in the low pressure
range. Hence, the value of KH for GNC-04 system is at least 1000 times greater than for the other ones. Forthree of the remaining structures (i.e., GNC-11, GNC-15 and GNC-18), lower values of KH (< 104 mmol/g)
are recorded. The same carbons have the lowest enthalpy of adsorption at zero coverage.
Figure 6 presents comparison of αs-plots related to the Ar adsorption isotherms. One can see that theadsorption process is dominated by a FS swings (GNC-04 and GNC-07) and the FS-CS swings (remaining
structures) [98]. It can be noticed that with the rise in the pore diameter, the combination of primary
and secondary micropore filling mechanism occurs. The boundary between those mechanisms is located
for the structures with pore diameters around ca. 0.8 nm. It is also interesting that the range on αs-plotsconnecting FS and CS swings is not linear as it is observed for the case of slit-like carbon micropores. This
can be caused by the surface curvature.
Figure 7 (a) compares APD curves for all the systems studied. The presented data are complemen-
tary to adsorption isotherms shown in figure 2. On all the APD curves, at least one (dominant) peak is
observed. It corresponds to the pore filling. Its location [Apot,max, figure 7 (b)] is related to the pressureof the pore filling according to equation 2.1. Hence, this parameter may be correlated with the size of
pores — see figure 7 (c). This figure quantitatively confirms the above-described qualitative differences
in the pore filling process. The width of the main peak also provides some information on the process.
The narrow peak means that condensation occurs in a narrow range of relative pressure. By contrast, a
wide peak denotes a wide condensation range. For example, the pore filling in GNC-04 system occurs, as
mentioned above, for 10−8 < p/ps < 10−6 and this is reflected by a wide peak with the maximum located
at ca. 12.6 kJ/mol. For this system, the other two peaks are also observed (the third onewith themaximum
13003-8
Gyroidal nanoporous carbons— Adsorption and separation properties
Figure 8. (Color online) Comparison of equilibrium separation factors [S1/2, equation (2.2)] for the ad-sorption of all the mixtures (T = 298 K, ptot = 0.1 MPa) on all the nanocarbons studied. The data plotted
as the function of the 1st component mol fraction in the gaseous phase (y1, the 1st component is CO2 forCO2/CH4 and CO2/N2 mixtures and CH4 for CH4/N2 mixture).
at ca. 45 kJ/mol is very broad). These peaks reflect the other sub-steps of the Ar density rise in pores of this
structure. Similar interpretation also concerns the additional peaks observed for GNC-11 and GNC-12. In
the case of GNC-18 and GNC-21 structures, the observed second peak is related to the above mentioned
monolayer formation. A slightly different scenario occurs for GNC-15 carbon. Here, the dominant peak
is connected with the monolayer formation and the second low (also wide) peak reflects the filling of the
remaining pore volume. This fact explains why the location of the main peak for this structure deviates
from the distinct trend visible for all the other GNCs in correlation shown in figure 7 (c).
Figure 8 presents a comparison of equilibrium separation factors for adsorption of all three studied
mixtures for different compositions of gaseous phase. In addition, figure 9 directly compares the effi-
ciency of separation of equimolar mixtures for all the studied systems. The separation is a consequence
of differences in the adsorption of mixture components. Since the critical temperature for the studied
gases decreases significantly in the sequence CO2 > CH4 > N2, the adsorption affinity decreases in the
13003-9
S. Furmaniak et al.
Figure 9. (Color online) Comparison of equilibrium separation factors for adsorption of equimolar
(y = 0.5) mixtures: (a) CO2/CH4, (b) CO2/N2 and (c) CH4/N2 (ptot = 0.1MPa, T = 298 K)— see figure 8.
same sequence (for the subsequent gases, the process occurs for increasing value of reduced tempera-
ture). Consequently, for the given GNC, the highest equilibrium separation factor is observed for CO2/N2and the smallest one for CH4/N2 mixture. The qualitative differences in separation efficiency between thestructures studied are the same for all the mixtures studied. The highest values of equilibrium separation
factor (remarkably higher than for the other systems) are observed for GNC-04 carbon. This is connected
Figure 10. (Color online) Comparison of equilibrium separation factors [(a) CO2/CH4, (b) CO2/N2 and (c)CH4/N2] for mixture adsorption (ptot = 0.1 MPa, T = 298 K) on GNC-04 and GNC-21 nanocrabons and on
three virtual porous carbons (VPCs): d0.5, d0.9 and d1.3 [88] (the data for VPCs taken from our previous
paper [60]). In addition, panel (d) presents the pore size histograms for the presented VPCs [88] (the
subsequent histograms are shifted by 0.15 units from the previous ones).
13003-10
Gyroidal nanoporous carbons— Adsorption and separation properties
with the presence of the narrowest pores. Among the other nanocarbons, GNC-07 and GNC-09 also ex-
hibit higher values of S1/2. However, they are lower than in the case of GNC-04 since these structureshave wider pores. The efficiency of separation for the next GNCs is similar. Nevertheless, some small dif-
ferences are also noticeable (see insets in figure 9). The GNC-11, GNC-15 and GNC-18 structures are less
efficient in comparison with the adjacent carbons in the series. These regularities are analogous to that
observed for Henry’s constants shown in figure 5 and discussed above. These facts suggest that in the
case of GNCs with pores wider than ca. 1 nm, the main factor affecting the efficiency of the separation
process is the energetics of fluid interaction with the curved surface of the nanocarbons studied.
Finally, figure 10 compares the equilibrium separation factors (all three mixtures studied) for GNC-04
and GNC-21 structures and for three virtual porous carbons (VPCs) described in detail previously [88]
and having different porosity — see figure 10 (d). As one can see, the GNC-21 structure exhibits a sep-
aration efficiency similar to the d0.5 carbon. The main pores of both adsorbents have a similar width.
However, this VPC has also some narrower micropores which presence probably positively affects the
separation efficiency. Such micropores are absent in the case of GNC-21 and, nonetheless, this nanocar-
bon exhibits similar values of S1/2. This is the consequence of the adsorption energetics on a curvedsurface of this structure. On the contrary, the GNC-04 nanocarbon exhibits the efficiency of the CO2/CH4mixture separation similar to the d1.3 carbon. This VPC has micropores distributed in the range up to
ca. 1 nm [figure 10 (d)]. A large part of them has diameters similar to or lower than the GNC-04 struc-
ture. In the case of CO2/N2 and CH4/N2 mixtures, the values of equilibrium separation factors for GNC-04are higher than for d1.3 carbon. This comparison (especially for CO2/CH4 mixture — similar efficiencyfor both adsorbents and for CH4/N2 mixture — higher efficiency for GNC-04) may suggest that a regu-
larly curved surface of gyroidal carbons exhibits higher affinity to CH4 molecules than a heterogeneoussurface of activated carbons.
Summing up, the GNCs studiedmay be considered as potential adsorbents for gas mixture separation.
The efficiency of this process is similar to or higher than for activated carbons with similar diameters of
pores. The GNC-04 or similar structures seem to be quite promising materials for this purpose since this
nanocarbon contains narrow and quite uniform pores (ca. 0.5 nm).
4. Conclusions
Adsorption and separation properties of GNCs— a new class of exotic nanocarbonmaterials, are stud-
ied for the first time using computer simulation technique. All the structures studied are strictly micro-
porous. The mechanisms of Ar adsorption are described basing on the analysis of adsorption isotherms,
enthalpy plots, the values of Henry’s constants, αs and adsorption potential distribution plots. Below thepore diameters ca. 0.8 nm, primary micropore filling process dominates. For structures possessing larger
micropores, primary and secondary micropore filling mechanisms are observed. GNCs may be consid-
ered as potential adsorbents for gas mixture separation, having separation efficiency similar to or higher
than this for activated carbons with similar diameters of pores.
Acknowledgements
The authors acknowledge the use of the computer cluster at Poznań Supercomputing and Network-
ing Centre (Poznań, Poland) as well as the Information and Communication Technology Centre of the
Nicolaus Copernicus University (Toruń, Poland).
References
1. Gas Separation by Adsorption Processes, Series on Chemical Engineering Vol. 1, Yang R.T. (Ed.), Imperial College
Press, London, 1997.
2. Ruthven D.M., Farooq S., Knaebel K.S., Pressure Swing Adsorption, Wiley-VCH, New York, 1994.
3. Sinaiski E.G., Lapiga E.J., Separation of Multiphase, Multicomponent Systems, Wiley-VCH, Weinheim, 1997.
4. Jaroniec M., Madey R., Physical Adsorption on Heterogeneous Solids, Elsevier, New York, 1988.
13003-11
S. Furmaniak et al.
5. Rudziński W., Everett D.H., Adsorption of Gases on Heterogeneous Surfaces, Academic Press, New York, 1992.
6. Rouquerol F., Rouquerol J., Sing K.S.W., Llewellyn P., Maurin G., Adsorption by Powders and Porous Solids.
Principles, Methodology and Applications, 2nd Edn., Elsevier, Amsterdam, 2014;
doi:10.1016/B978-0-08-097035-6.09991-5.
7. Bansal R.C., Goyal M., Activated Carbon Adsorption, CRC Press, Boca Raton, 2005.
8. Palmer J.C., Moore M.V., Roussel T.J., Brennan J.K., Gubbins K.E., Phys. Chem. Chem. Phys., 2011, 13, 3985;
doi:10.1039/c0cp02281k.
9. Liu L., Nicholson D., Bhatia S.K., J. Phys. Chem. C, 2015, 119, 407; doi:10.1021/jp5099987.
10. Ozturk T.N., Keskin S., Ind. Eng. Chem. Res., 2013, 52, 17627; doi:10.1021/ie403159c.
11. Lu X., Jin D., Wei S., Wang Z., An C., Guo W., J. Mater. Chem. A, 2015, 3, 12118; doi:10.1039/C4TA06829G.
12. Billemont P., Coasne B., De Weireld G., Adsorption, 2014, 20, 453; doi:10.1007/s10450-013-9570-z.
13. Furmaniak S., Terzyk A.P., Kaneko K., Gauden P.A., Kowalczyk P., Ohba T., Chem. Phys. Lett., 2014, 595-596, 67;
doi:10.1016/j.cplett.2014.01.031.
14. Di Biase E., Sarkisov L., Carbon, 2015, 94, 27; doi:10.1016/j.carbon.2015.06.056.
15. Borówko M., Patrykiejew A., Rżysko W., Sokołowski S., Langmuir, 1997, 13, 1073; doi:10.1021/la950940a.
16. Grabowski K., Patrykiejew A., Sokołowski S., Thin Solid Films, 1999, 352, 259; doi:10.1016/S0040-6090(99)00291-6.
17. Grabowski K., Patrykiejew A., Sokołowski S., Thin Solid Films, 2000, 379, 297; doi:10.1016/S0040-6090(00)01398-5.
18. Patrykiejew A., Sałamacha L., Sokołowski S., Pizio O., Phys. Rev. E, 2003, 67, 061603;
doi:10.1103/PhysRevE.67.061603.
19. Patrykiejew A., Sałamacha L., Sokołowski S., Dominguez H., Pizio O., Phys. Rev. E, 2003, 67, 031202;
doi:10.1103/PhysRevE.67.031202.
20. Patrykiejew A., Sokołowski S., Pizio O., J. Phys. Chem. B, 2005, 109, 14227; doi:10.1021/jp048170b.
21. Patrykiejew A., Sokołowski S., Phys. Rev. E, 2010, 81, 012501; doi:10.1103/PhysRevE.81.012501.
22. Patrykiejew A., Sokołowski S., J. Chem. Phys., 2012, 136, 144702; doi:10.1063/1.3699330.
23. Bryk P., Sokołowski S., Pizio O., J. Phys. Chem. B, 1999, 103, 3366; doi:10.1021/jp982028r.
24. Noworyta J.P., Henderson D., Sokołowski S., Chan K.-Y., Mol. Phys., 1998, 95, 415; doi:10.1080/00268979809483175.
25. Patrykiejew A., Pizio O., Pusztai L., Sokołowski S., Mol. Phys., 2003, 101, 2219; doi:10.1080/0026897031000099925.
26. Patrykiejew A., Pizio O., Sokołowski S., Sokołowska Z., Phys. Rev. E, 2004, 69, 061605;
doi:10.1103/PhysRevE.69.061605.
27. Bryk P., Sokołowski S., J. Chem. Phys., 2004, 120, 8299; doi:10.1063/1.1695554.
28. Pizio O., Sokołowski S., Sokołowska Z., J. Chem. Phys., 2011, 134, 214702; doi:10.1063/1.3597773.
29. Ilnytskyi J.M., Patsahan T., Sokołowski S., J. Chem. Phys., 2011, 134, 204903; doi:10.1063/1.3592562.
30. Bryk P., Pizio O., Sokołowski S., J. Chem. Phys., 2005, 122, 174906; doi:10.1063/1.1888425.
31. Pizio O., Bucior K., Patrykiejew A., Sokołowski S., J. Chem. Phys., 2005, 123, 214902; doi:10.1063/1.2128701.
32. Sokołowski S., Rżysko W., Pizio O., J. Colloid Interface Sci., 1999, 218, 341; doi:10.1006/jcis.1999.6392.
33. Kruk M., Patrykiejew A., Sokołowski S., Surf. Sci., 1995, 340, 179; doi:10.1016/0039-6028(95)00681-8.
34. Martinez A., Patrykiejew A., Pizio O., Sokołowski S., J. Phys.: Condens. Matter, 2003, 15, 3107;
doi:10.1088/0953-8984/15/19/312.
35. Grabowski K., Patrykiejew A., Sokołowski S., Thin Solid Films, 1997, 304, 344; doi:10.1016/S0040-6090(97)00214-9.
36. Kruk M., Patrykiejew A., Sokołowski S., Thin Solid Films, 1994, 238, 302; doi:10.1016/0040-6090(94)90071-X.
37. Bucior K., Patrykiejew A., Pizio O., Sokołowski S., J. Colloid Interface Sci., 2003, 259, 209;
doi:10.1016/S0021-9797(02)00203-5.
38. Martinez A., Pizio O., Sokołowski S., J. Chem. Phys., 2003, 118, 6008; doi:10.1063/1.1556850.
39. Sałamacha L., Patrykiejew A., Sokołowski S., J. Phys. Chem. B, 2009, 113, 13687; doi:10.1021/jp901383v.
40. Patrykiejew A., Sokołowski S., J. Phys. Chem. B, 2010, 114, 396; doi:10.1021/jp908710e.
41. Patrykiejew A., Sokołowski S., Condens. Matter Phys., 2014, 17, 43601; doi:10.5488/CMP.17.43601.
42. Patrykiejew A., Rżysko W., Sokołowski S., J. Phys. Chem. C, 2012, 116, 753; doi:10.1021/jp208323b.
43. Pizio O., Rżysko W., Sokołowski S., Sokołowska Z., J. Chem. Phys., 2015, 142, 164703; doi:10.1063/1.4918640.
44. Suarez-Martinez I., Grobert N., Ewels C.P., Carbon, 2012, 50, 741; doi:10.1016/j.carbon.2011.11.002.
45. Georgakilas V., Perman J.A., Tucek J., Zboril R., Chem. Rev., 2015, 115, 4744; doi:10.1021/cr500304f.
46. Tomanek D., Guide Through the Nanocarbon Jungle, Morgan and Claypool Publishers, San Rafael, 2014.
47. Carbon Nanomaterials as Adsorbents for Environmental and Biological Applications, Carbon Nanostructures
Series, Bergmann C.P., Machado F. (Eds.), Springer International Publishing, New York, 2015;
doi:10.1007/978-3-319-18875-1.
48. Gogotsi Y., Presser V., Carbon Nanomaterials, CRC Press, Boca Raton, 2013.
49. Yeganegi S., Gholampour F., Acta Chim. Slov., 2012, 59, 888.
50. Kowalczyk P., Chem. Phys. Phys. Chem., 2012, 14, 2784; doi:10.1039/c2cp23445a.
13003-12
http://dx.doi.org/10.1016/B978-0-08-097035-6.09991-5
http://dx.doi.org/10.1039/c0cp02281k
http://dx.doi.org/10.1021/jp5099987
http://dx.doi.org/10.1021/ie403159c
http://dx.doi.org/10.1039/C4TA06829G
http://dx.doi.org/10.1007/s10450-013-9570-z
http://dx.doi.org/10.1016/j.cplett.2014.01.031
http://dx.doi.org/10.1016/j.carbon.2015.06.056
http://dx.doi.org/10.1021/la950940a
http://dx.doi.org/10.1016/S0040-6090(99)00291-6
http://dx.doi.org/10.1016/S0040-6090(00)01398-5
http://dx.doi.org/10.1103/PhysRevE.67.061603
http://dx.doi.org/10.1103/PhysRevE.67.031202
http://dx.doi.org/10.1021/jp048170b
http://dx.doi.org/10.1103/PhysRevE.81.012501
http://dx.doi.org/10.1063/1.3699330
http://dx.doi.org/10.1021/jp982028r
http://dx.doi.org/10.1080/00268979809483175
http://dx.doi.org/10.1080/0026897031000099925
http://dx.doi.org/10.1103/PhysRevE.69.061605
http://dx.doi.org/10.1063/1.1695554
http://dx.doi.org/10.1063/1.3597773
http://dx.doi.org/10.1063/1.3592562
http://dx.doi.org/10.1063/1.1888425
http://dx.doi.org/10.1063/1.2128701
http://dx.doi.org/10.1006/jcis.1999.6392
http://dx.doi.org/10.1016/0039-6028(95)00681-8
http://dx.doi.org/10.1088/0953-8984/15/19/312
http://dx.doi.org/10.1016/S0040-6090(97)00214-9
http://dx.doi.org/10.1016/0040-6090(94)90071-X
http://dx.doi.org/10.1016/S0021-9797(02)00203-5
http://dx.doi.org/10.1063/1.1556850
http://dx.doi.org/10.1021/jp901383v
http://dx.doi.org/10.1021/jp908710e
http://dx.doi.org/10.5488/CMP.17.43601
http://dx.doi.org/10.1021/jp208323b
http://dx.doi.org/10.1063/1.4918640
http://dx.doi.org/10.1016/j.carbon.2011.11.002
http://dx.doi.org/10.1021/cr500304f
http://dx.doi.org/10.1007/978-3-319-18875-1
http://dx.doi.org/10.1039/c2cp23445a
Gyroidal nanoporous carbons— Adsorption and separation properties
51. Furmaniak S., Terzyk A.P., Kowalczyk P., Kaneko K., Gauden P.A., Chem. Phys. Phys. Chem., 2013, 15, 16468;
doi:10.1039/c3cp52342j.
52. Furmaniak S., Terzyk A.P., Gauden P.A., Kowalczyk P., Harris P.J.F., J. Phys.: Condens. Matter, 2014, 26, 485006;
doi:10.1088/0953-8984/26/48/485006.
53. Kowalczyk P., Terzyk A.P., Gauden P.A., Furmaniak S., Kaneko K., Miller T.F., J. Phys. Chem. Lett., 2015, 6, 3367;
doi:10.1021/acs.jpclett.5b01545.
54. Tanaka H., Kanoh H., YudasakaM., Iijima S., Kaneko K., J. Am. Chem. Soc., 2005, 127, 7511; doi:10.1021/ja0502573.
55. Romo-Herrera J.M., Terrones M., Terrones H., Dag S., Meunier V., Nano Lett., 2007, 7, 570; doi:10.1021/nl0622202.
56. Liu L., Nicholson D., Bhatia S.K., Chem. Eng. Sci., 2015, 121, 268; doi:10.1016/j.ces.2014.07.041.
57. Terzyk A.P., Furmaniak S., Gauden P.A., Harris P.J.F., Wloch J., Kowalczyk P., J. Phys.: Condens. Matter, 2007, 19,
406208; doi:10.1088/0953-8984/19/40/406208.
58. Terzyk A.P., Furmaniak S., Harris P.J.F., Gauden P.A., Wloch J., Kowalczyk P., Rychlickia G., Chem. Phys. Phys.
Chem., 2007, 9, 5919; doi:10.1039/b710552e.
59. Kowalczyk P., Gauden P.A., Terzyk A.P., Furmaniak S., Harris P.J.F., J. Phys. Chem. C, 2012, 116, 13640;
doi:10.1021/jp302776z.
60. Furmaniak S., Koter S., Terzyk A.P., Gauden P.A., Kowalczyk P., Rychlickia G., Chem. Phys. Phys. Chem., 2015, 17,
7232; doi:10.1039/c4cp05498a.
61. Palmer J.C., Moore J.D., Roussel T.J., Brennan J.K., Gubbins K.E., Chem. Phys. Phys. Chem., 2011, 13, 3985;
doi:10.1039/c0cp02281k.
62. Furmaniak S., Kowalczyk P., Terzyk A.P., Gauden P.A., Harris P.J.F., J. Colloid Interface Sci., 2013, 397, 144;
doi:10.1016/j.jcis.2013.01.044.
63. Lu L., Wang S., Muller E.A., Cao W., Zhu Y., Lu X., Jackson G., Fluid Phase Equilib., 2014, 362, 227;
doi:10.1016/j.fluid.2013.10.013.
64. Kowalczyk P., Hołyst R., Terrones M., Terrones H., Phys. Chem. Chem. Phys., 2007, 9, 1786; doi:10.1039/b618747a.
65. Mackay A.L., Nature, 1985, 314, 604; doi:10.1038/314604a0.
66. Mackay A.L., Terrones H., Nature, 1991, 352, 762; doi:10.1038/352762a0.
67. Lijma S., Ichihashi T., Ando Y., Nature, 1992, 356, 776; doi:10.1038/356776a0.
68. Schwartz H.A., Gesammelte Mathematische Abhandlunge, Vol. 1 and 2, Springer, Berlin, 1980.
69. Townsend S.J., Lenosky T.J., Muller D.A., Nichols C.S., Elser V., Phys. Rev. Lett., 1992, 69, 921;
doi:10.1103/PhysRevLett.69.921.
70. Lee H.G., Kim J., Int. J. Numer. Methods Eng., 2012, 91, 269; doi:10.1002/nme.4262.
71. Hu M., Tian F., Zhao Z., Huang Q., Xu B., Wang L.-M., Wang H.-T., Tian Y., He J., J. Phys. Chem. C, 2012, 116, 24233;
doi:10.1021/jp3064323.
72. Kowalczyk P., He J., Hu M., Gauden P.A., Furmaniak S., Terzyk A.P., Phys. Chem. Chem. Phys., 2013, 15, 17366;
doi:10.1039/c3cp52708e.
73. Kowalczyk P., Parsons D., Terzyk A.P., Gauden P.A., Furmaniak S., In: Carbon Nanomaterials Sourcebook:
Nanoparticles, Nanocapsules, Nanofibers, Nanoporous Structures, and Nanocomposites, Vol. 2, Sattler K.D. (Ed.),
CRC Press, London, 2016, ch. 6 (in press).
74. Tylianakis E., Dimitrakakis G.K., Martin-Martinez F.J., Melchor S., Dobado J.A., Klontzas E., Froudakis G.E., Int. J.
Hydrogen Energy, 2014, 39, 9825; doi:10.1016/j.ijhydene.2014.03.011.
75. Wang H., Cao D., J. Phys. Chem. C, 2015, 119, 6324; doi:10.1021/jp512275p.
76. Huang L., Yang X., Cao D., J. Phys. Chem. C, 2015, 119, 3260; doi:10.1021/jp5128404.
77. Yang Z., Peng X., Cao D., J. Phys. Chem. C, 2013, 117, 8353; doi:10.1021/jp402488r.
78. Huang L., Xiang Z., Cao D., J. Mater. Chem. A, 2013, 1, 3851; doi:10.1039/c3ta10292k.
79. Huang L., Zeng X., Cao D., J. Mater. Chem. A, 2014, 2, 4899; doi:10.1039/C3TA15062C.
80. Karfunkel H.R., Dressler T., J. Am. Chem. Soc., 1992, 114, 2285; doi:10.1021/ja00033a001.
81. Zhao Z.S., Xu B., Wang L.M., Zhou X.F., He J.L., Liu Z.Y., Wang H.T., Tian Y.J., ACS Nano, 2011, 5, 7226;
doi:10.1021/nn202053t.
82. Ribeiro F.J., Tangney P., Louie S.G., Cohen M.L., Phys. Rev. B, 2006, 74, 172101; doi:10.1103/PhysRevB.74.172101.
83. Furmaniak S., Terzyk A.P., Gauden P.A., Wloch J., Kowalczyk P., Werengowska-Ciećwierz K., Wiśniewski M., Har-
ris P.J.F., J. Phys.: Condens. Matter, 2015, 28, 015002; doi:10.1088/0953-8984/28/1/015002.
84. Nicolaï A., Monti J., Daniels C., Meunier V., J. Phys. Chem. C, 2015, 119, 2896; doi:10.1021/jp511919d.
85. Werner J.G., Hoheisel T.N., Wiesner U., ACS Nano, 2014, 8, 731; doi:10.1021/nn405392t.
86. Choudhury S., Agrawal M., Formanek P., Jehnichen D., Fischer D., Krause B., Albrecht V., StammM., Ionov L., ACS
Nano, 2015, 9, 6147; doi:10.1021/acsnano.5b01406.
87. Bhattacharya S., Gubbins K.E., Langmuir, 2006, 22, 7726; doi:10.1021/la052651k.
88. Furmaniak S., Comput. Meth. Sci. Technol., 2013, 19, 47; doi:10.12921/cmst.2013.19.01.47-57.
13003-13
http://dx.doi.org/10.1039/c3cp52342j
http://dx.doi.org/10.1088/0953-8984/26/48/485006
http://dx.doi.org/10.1021/acs.jpclett.5b01545
http://dx.doi.org/10.1021/ja0502573
http://dx.doi.org/10.1021/nl0622202
http://dx.doi.org/10.1016/j.ces.2014.07.041
http://dx.doi.org/10.1088/0953-8984/19/40/406208
http://dx.doi.org/10.1039/b710552e
http://dx.doi.org/10.1021/jp302776z
http://dx.doi.org/10.1039/c4cp05498a
http://dx.doi.org/10.1039/c0cp02281k
http://dx.doi.org/10.1016/j.jcis.2013.01.044
http://dx.doi.org/10.1016/j.fluid.2013.10.013
http://dx.doi.org/10.1039/b618747a
http://dx.doi.org/10.1038/314604a0
http://dx.doi.org/10.1038/352762a0
http://dx.doi.org/10.1038/356776a0
http://dx.doi.org/10.1103/PhysRevLett.69.921
http://dx.doi.org/10.1002/nme.4262
http://dx.doi.org/10.1021/jp3064323
http://dx.doi.org/10.1039/c3cp52708e
http://dx.doi.org/10.1016/j.ijhydene.2014.03.011
http://dx.doi.org/10.1021/jp512275p
http://dx.doi.org/10.1021/jp5128404
http://dx.doi.org/10.1021/jp402488r
http://dx.doi.org/10.1039/c3ta10292k
http://dx.doi.org/10.1039/C3TA15062C
http://dx.doi.org/10.1021/ja00033a001
http://dx.doi.org/10.1021/nn202053t
http://dx.doi.org/10.1103/PhysRevB.74.172101
http://dx.doi.org/10.1088/0953-8984/28/1/015002
http://dx.doi.org/10.1021/jp511919d
http://dx.doi.org/10.1021/nn405392t
http://dx.doi.org/10.1021/acsnano.5b01406
http://dx.doi.org/10.1021/la052651k
http://dx.doi.org/10.12921/cmst.2013.19.01.47-57
S. Furmaniak et al.
89. Furmaniak S., Terzyk A.P., Gauden P.A., Kowalczyk P., Harris P.J.F., Koter S., J. Phys.: Condens. Matter, 2013, 25,
015004; doi:10.1088/0953-8984/25/1/015004.
90. Yan Q., de Pablo J.J., J. Chem. Phys., 1999, 111, 9509; doi:10.1063/1.480282.
91. Frenkel D., Smit B., Understanding Molecular Simulation, Academic Press, San Diego, 1996.
92. Setoyama N., Suzuki T., Kaneko K., Carbon, 1998, 36, 1459; doi:10.1016/S0008-6223(98)00138-9.
93. Kruk M., Jaroniec M., Gadkaree K.P., Langmuir, 1999, 15, 1442; doi:10.1021/la980789f.
94. Choma J., Jaroniec M., Colloids Surf. A, 2001, 189, 103; doi:10.1016/S0927-7757(01)00572-6.
95. Choma J., Jaroniec M., Adsorpt. Sci. Technol., 2007, 25, 573; doi:10.1260/0263-6174.25.8.573.
96. Tylianakis E., Froudakis G.E., J. Comput. Theor. Nanosci., 2009, 6, 335; doi:10.1166/jctn.2009.1040.
97. Humphrey W., Dalke A., Schulten K., J. Mol. Graphics, 1996, 14, 33; doi:10.1016/0263-7855(96)00018-5.
98. Kaneko K., Ishii C., Kanoh H., Hanzawa Y., Setoyama N., Suzuki T., Adv. Colloid Interface Sci., 1998, 77, 295;
doi:10.1016/S0001-8686(98)00050-5.
Гiроїднi нанопористi вуглецi— адсорбцiя i особливостi
роздiлення, дослiдженi з використанням
комп’ютерного моделювання
С. Фурманяк1, П.А. Гауден1, А.П. Тержик1, П. Ковальчик2
1 Хiмiчний факультет, Дослiдницька група фiзикохiмiї вуглецевих матерiалiв,
Унiверситет Нiколауса Копернiкуса в Торунi, Торунь, Польща
2 Школа iнженерiї та iнформацiйних технологiй, Унiверситет Мердока,
Мердок, Захiдна Австралiя, 6150, Австралiя
Адсорбцiя i особливостi роздiлення у гiроїдних нанопористих вуглецях (GNC), новому класi екзотичних
нановуглецевих матерiалiв, вперше дослiджено, використовуючи метод моделювання Монте Карло з гi-
перпаралельним темперуванням. Пориста структура GNC моделей оцiнюється методом, запропонова-
ним Бхатачарiя i Губiнсом. Всi дослiдженi структури є строго мiкропористi. Крiм того, механiзми адсорбцiї
Ar описуються на основi аналiзу iзотерм адсорбцiї, кривих ентальпiї, значень сталих Генрi, αs та кри-
вих розподiлу потенцiалу адсорбцiї. Зроблено висновок, що при дiаметрах пор близьких або менших
за 0.8 nm домiнує процес заповнення первинних мiкропор. Для структур, що мають бiльшi мiкропори,
спостерiгається механiзм заповнення первинних та вторинних мiкропор. Нарештi, описано властивостi
роздiлення CO2/CH4, CO2/N2 i CH4/N2 сумiшей у GNC i виконано порiвняння з властивостями роздiлення
моделей Вiртуального Пористого Вуглецю. Гiроїднi пористi вуглецi можна розглядати як потенцiйнi ад-
сорбенти для роздiлення газових сумiшей, якi володiють аналогiчною або навiть вищою ефективнiстю
роздiлення, нiж активований вуглець з подiбним дiаметром пор.
Ключовi слова: гiроїднi нанопористi вуглецi, адсорбцiя, роздiлення газових сумiшей, моделювання
Монте Карло
13003-14
http://dx.doi.org/10.1088/0953-8984/25/1/015004
http://dx.doi.org/10.1063/1.480282
http://dx.doi.org/10.1016/S0008-6223(98)00138-9
http://dx.doi.org/10.1021/la980789f
http://dx.doi.org/10.1016/S0927-7757(01)00572-6
http://dx.doi.org/10.1260/0263-6174.25.8.573
http://dx.doi.org/10.1166/jctn.2009.1040
http://dx.doi.org/10.1016/0263-7855(96)00018-5
http://dx.doi.org/10.1016/S0001-8686(98)00050-5
Introduction
Simulation details
Results and discussion
Conclusions
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