Adsorption In Porous Materials Research Articles

Flat-Histogram Monte Carlo Simulation of Water Adsorption in Metal-Organic Frameworks.

Molecular simulations of water adsorption in porous materials often converge slowly due to sampling bottlenecks that follow from hydrogen bonding and, in many cases, the formation of water clusters. These effects may be exacerbated in metal-organic framework (MOF) adsorbents, due to the presence of pore spaces (cages) that promote the formation of discrete-size clusters and hydrophobic effects (if present), among other reasons. In Grand Canonical Monte Carlo (MC) simulations, these sampling challenges are typically manifested by low MC acceptance ratios, a tendency for the simulation to become stuck in a particular loading state (i.e., macrostates), and the persistence of specific clusters for long periods of the simulation. We present simulation strategies to address these sampling challenges, by applying flat-histogram MC (FHMC) methods and specialized MC move types to simulations of water adsorption. FHMC, in both Transition-matrix and Wang-Landau forms, drives the simulation to sample relevant macrostates by incorporating weights that are self-consistently adjusted throughout the simulation and generate the macrostate probability distribution (MPD). Specialized MC moves, based on aggregation-volume bias and configurational bias methods, separately address low acceptance ratios for basic MC trial moves and specifically target water molecules in clusters; in turn, the specialized MC moves improve the efficiency of generating new configurations which is ultimately reflected in improved statistics collected by FHMC. The combined strategies are applied to study the adsorption of water in CuBTC and ZIF-8 at 300 K, through examination of the MPD and the adsorption isotherm generated by histogram reweighting. A key result is the appearance of nontrivial oscillations in the MPD, which we show to be associated with water clusters in the adsorption system. Additionally, we show that the probabilities of certain clusters become similar in value near the boundaries of the isotherm hysteresis loop, indicating a strong connection between cluster formation/destruction and the thermodynamic limits of stability. For a hydrophobic MOF, the FHMC results show that the phase transition from low density to high density is suppressed to water pressure far above the bulk-fluid saturation pressure; this is consistent with results presented elsewhere. We also compare our FHMC simulation isotherm to one measured by a different technique but with ostensibly the same molecular interactions and comment on observed differences and the need for follow-up work. The simulation strategies presented here can be applied to the simulation of water in other MOFs using heuristic guidelines laid out in our text, which should facilitate the more consistent and efficient simulation of water adsorption in porous materials in future applications.

Computing Mixture Adsorption in Porous Materials through Flat Histogram Monte Carlo Methods.

Mixture adsorption properties of porous materials are critical to determine their potential as adsorbents in separation applications. Toward the discovery of optimal adsorbents, in silico screening studies typically employ the grand canonical Monte Carlo (GCMC) technique to compute adsorption properties of gas mixtures in materials of interest at a given condition (i.e., composition, total pressure, and temperature) or to compute their adsorption properties for each component, followed by utilizing methods to predict mixture adsorption isotherms. However, the former approach results in the need for repeated calculations when different conditions such as compositions are considered. For the latter, the predictions may involve uncertainties, sometimes originating from the fitting quality to the pure component isotherms, and repeated simulations may also be needed for different temperatures. To this end, this study demonstrates the potential of flat histogram Monte Carlo methods in addressing the abovementioned shortfalls. Specifically, the so-called NVT + W method, first reported by Smit and co-workers, is extended herein to determine the macrostate probability distribution (MPD) of binary mixtures in porous materials. The obtained MPD can be reweighted to any conditions, yielding accurate adsorption isotherms of any desired compositions and temperatures. This approach, denoted as 2D NVT + W, is also compared with the widely adopted ideal adsorbed solution theory (IAST) method, and the former is found to offer more reliable predictions. Overall, the 2D NVT + W approach represents an efficient and effective alternative to compute mixture adsorption isotherms for porous materials, and the obtained MPD can be conveniently reused by peer researchers. A user-friendly Python code is also provided along with this article to employ this method.

Preparation of microporous carbonaceous CO2 adsorbents by activating bamboo shoot shells with different chlorides: Experimental and theoretical calculations

In this paper, a series of microporous carbonaceous adsorbents were prepared using bamboo shoot shells as carbon precursors and four different chlorides (calcium chloride, potassium chloride, iron chloride and zinc chloride) as activators. The results show that the pore structure and specific surface area of the adsorbent jointly affect the adsorption capacity of CO2. The porous carbon prepared with calcium chloride and potassium chloride as the activator has the highest micropore content, reaching more than 93 %. The solid adsorbent BSSC-CaCl2-700 with calcium chloride as the activator exhibited the highest CO2 adsorption capacity of 70.45 cm3/g and 53.62 cm3/g at 273 K and 298 K under 1 bar, respectively. It is a promising adsorbent for CO2 capture from flue gas. Based on the experimental study, a model of porous carbon prepared by different activators was developed. Combined with the mechanism of CO2 adsorption in porous materials, the binding adsorption energy and self-diffusion coefficient of porous carbon prepared by the different chlorides as activators were calculated by DFT method. The results show that the adsorption energy of porous carbon with calcium chloride as an activator is − 8.1 KJ/mol, and the self-diffusion coefficients are 8 × 10−7 and 1.3 × 10−7 at 273 K and 298 K, respectively. The fitted R2 was both greater than 0.95. Therefore, the selected model can better illustrate that chloride has a stronger effect on the preparation of microporous biomass carbon, which provides an idea for subsequent experiments and theoretical research.

Direct Visualization of Supramolecular Binding and Separation of Light Hydrocarbons in MFM-300(In).

The purification of light olefins is one of the most important chemical separations globally and consumes large amounts of energy. Porous materials have the capability to improve the efficiency of this process by acting as solid, regenerable adsorbents. However, to develop translational systems, the underlying mechanisms of adsorption in porous materials must be fully understood. Herein, we report the adsorption and dynamic separation of C2 and C3 hydrocarbons in the metal–organic framework MFM-300(In), which exhibits excellent performance in the separation of mixtures of ethane/ethylene and propyne/propylene. Unusually selective adsorption of ethane over ethylene at low pressure is observed, resulting in selective retention of ethane from a mixture of ethylene/ethane, thus demonstrating its potential for a one-step purification of ethylene (purity > 99.9%). In situ neutron powder diffraction and inelastic neutron scattering reveal the preferred adsorption domains and host–guest binding dynamics of adsorption of C2 and C3 hydrocarbons in MFM-300(In).

Comments on “Monte Carlo simulations for water adsorption in porous materials: Best practices and new insights”

AIChE JournalEarly View e17686 LETTER TO THE EDITOR Comments on “Monte Carlo simulations for water adsorption in porous materials: Best practices and new insights” Daniel W. Siderius, Corresponding Author Daniel W. Siderius daniel.siderius@nist.gov orcid.org/0000-0002-6260-7727 Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA Correspondence Daniel W. Siderius, Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA. Email: daniel.siderius@nist.gov Contribution: Conceptualization (equal), Data curation (equal), Formal analysis (equal), ​Investigation (equal), Methodology (equal), Software (equal), Validation (equal), Visualization (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this authorHarold W. Hatch, Harold W. Hatch orcid.org/0000-0003-2926-9145 Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA Contribution: Conceptualization (equal), Data curation (equal), Formal analysis (equal), ​Investigation (equal), Methodology (equal), Software (equal), Validation (equal), Visualization (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this authorJeffrey R. Errington, Jeffrey R. Errington orcid.org/0000-0003-0365-0271 Department of Chemical and Biological Engineering, University at Buffalo, Buffalo, New York, USA Contribution: ​Investigation (equal), Methodology (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this authorVincent K. Shen, Vincent K. Shen Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA Contribution: Conceptualization (equal), Formal analysis (equal), Funding acquisition (equal), ​Investigation (equal), Methodology (equal), Project administration (equal), Supervision (equal), Validation (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this author Daniel W. Siderius, Corresponding Author Daniel W. Siderius daniel.siderius@nist.gov orcid.org/0000-0002-6260-7727 Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA Correspondence Daniel W. Siderius, Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA. Email: daniel.siderius@nist.gov Contribution: Conceptualization (equal), Data curation (equal), Formal analysis (equal), ​Investigation (equal), Methodology (equal), Software (equal), Validation (equal), Visualization (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this authorHarold W. Hatch, Harold W. Hatch orcid.org/0000-0003-2926-9145 Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA Contribution: Conceptualization (equal), Data curation (equal), Formal analysis (equal), ​Investigation (equal), Methodology (equal), Software (equal), Validation (equal), Visualization (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this authorJeffrey R. Errington, Jeffrey R. Errington orcid.org/0000-0003-0365-0271 Department of Chemical and Biological Engineering, University at Buffalo, Buffalo, New York, USA Contribution: ​Investigation (equal), Methodology (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this authorVincent K. Shen, Vincent K. Shen Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland, USA Contribution: Conceptualization (equal), Formal analysis (equal), Funding acquisition (equal), ​Investigation (equal), Methodology (equal), Project administration (equal), Supervision (equal), Validation (equal), Writing - original draft (equal), Writing - review & editing (equal)Search for more papers by this author First published: 10 March 2022 https://doi.org/10.1002/aic.17686 This work is an official contribution of the National Institute of Standards and Technology; not subject to copyright in the United States. Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat No abstract is available for this article. Early ViewOnline Version of Record before inclusion in an issuee17686 RelatedInformation

Responses to the comments on “Monte Carlo simulations for water adsorption in porous materials: Best practices and new insights”

Responses to the comments on “Monte Carlo simulations for water adsorption in porous materials: Best practices and new insights”

Chemistry-Encoded Convolutional Neural Networks for Predicting Gaseous Adsorption in Porous Materials

Chemistry-Encoded Convolutional Neural Networks for Predicting Gaseous Adsorption in Porous Materials

Monte Carlo simulations for water adsorption in porous materials: Best practices and new insights

AbstractTechnologies based on water adsorption such as water harvesting from air have tremendous potential in mitigating important global crises such as water scarcity. An important challenge to the deployment of such technologies is finding optimal adsorbent materials. Given the large materials space of available adsorbents, large‐scale computational screening can be extremely helpful for this task. This work explores the methods and details associated with such screening procedures and recommends best practices. We also shed light on the limitations of traditionally used and inexpensive to compute prescreening approaches involving geometric and energetic features to predict water adsorption behavior of porous materials. Such approaches can provide general trends to predict adsorption behavior but may lead to the overlook of potentially important structures due to the complex nature of water adsorption. This study offers insights for future water adsorption simulations to facilitate the development of optimal water adsorbents.

Improving Computational Assessment of Porous Materials for Water Adsorption Applications via Flat Histogram Methods

Water adsorption in porous materials has recently drawn considerable attention for its tremendous potential in environmental applications such as water harvesting from air. A key step to the deployment of such technologies is the selection of optimal adsorbent materials as material performance directly impacts their efficiency. Owing to the vast materials space, computational studies may play a critically important role in facilitating the selection of the best material. The current state-of-the-art method to predict adsorption behavior of porous materials, the grand canonical Monte Carlo (GCMC) simulations, however, can converge very slowly due to its inefficient sampling of the phase space accessible to the system and may yield unreliable results. To this end, we have demonstrated a method from a class of techniques known as flat histogram methods, which can sample the accessible states of the system much more efficiently. Further, a so-called C-map method is proposed herein to efficiently determine the applicability of a material in water adsorption applications. These methods can offer unprecedented insights into the behaviors of the GCMC-predicted isotherms and, more importantly, are promising for large-scale computational screening of porous materials for water adsorption.

Metal organic frameworks for hydrogen purification

High purity hydrogen is one of the key factors in determining the lifetime of proton exchange membrane (PEM) fuel cells. However, the current industrial processes for producing high purity hydrogen are not only expensive, but also come with low energy efficiencies and productivity. Finding more cost-effective methods of purifying hydrogen is essential for ensuring wider scale deployment of PEM fuel cells. Among various hydrogen purification methods, adsorption in porous materials and membrane technologies are seen as two of the most promising candidates for the current industrial hydrogen purification methods, with metal organic frameworks (MOF) being particularly popular in research over the last decade. Despite many available reviews on MOFs, most focus on synthesis and production, with few reports focused on performance for hydrogen purification. This review describes the working principle and performance parameters of adsorptive separations and membrane materials and identifies MOFs that have been reported for hydrogen purification. The MOFs are summarised and their performance in separating hydrogen from common impurities (CO2, N2, CH4, CO) is compared systematically. The challenges of commercial application of MOFs for hydrogen purification are discussed.

Development of dual‐model classical density functional theory and its application to gas adsorption in porous materials

AbstractClassical density functional theory (CDFT) is a useful theory in many fields. The basis of CDFT is spherical model and extending it to nonspherical molecules is a challenging issue due to the orientation/configuration of the molecules, which implies more complicated molecular models, and higher computational costs. In this work, we propose a dual‐model classical density functional theory (DM‐CDFT) to address this issue. The theory uses a more precise model (all‐atom model) and a simpler model (coarsening model) to construct the external and excess free energy functionals, respectively. By using this methodology, CDFT could handle orientation/configuration effects with low computational costs. The theory is examined by applying it to gas adsorption (such as C2H2/C2H4/C2H6 and toxic gases) in porous materials, and the predicted adsorption isotherms verify the accuracy of the theory. Additionally, the predicted density profile indicates that rotation entropy plays an important role in the adsorption of nonspherical molecules.

A mini-review on the modeling of volatile organic compound adsorption in activated carbons: Equilibrium, dynamics, and heat effects

The research on the adsorption equilibria, kinetics, and increase in process temperature of the volatile organic compound (VOC) adsorption in porous materials ensures safe production, thereby reducing production costs and improving separation efficiency. Therefore, it is critical in predicting the entire adsorption process based on minimal or no experimental input of the adsorbate and adsorbent. We discuss, in this review, the factors that affect the adsorption performance of VOCs in activated carbons, including the adsorption equilibrium, adsorption kinetics, and exotherm during adsorption. Subsequently, the existing prediction models are summarized and compared concerning the adsorption equilibrium, adsorption kinetics, and exothermic process of adsorption. We then propose a new prediction model based on intermolecular interaction and provide an outlook toward the design and manipulation of efficient adsorbents for the VOC system.

How Reproducible Are Isotherm Measurements in Metal–Organic Frameworks?

Scientific progress is severely impeded if experimental measurements are not reproducible. Materials chemistry and related fields commonly report new materials with limited attention paid to reproducibility. Here, we describe methods that are well suited to assessing reproducibility in these fields via retrospective analysis of reported data. This concept is illustrated by an exhaustive analysis of a topic that has been the focus of thousands of published studies, gas adsorption in metal–organic framework (MOF) materials. We show that for the well-studied case of CO2 adsorption there are only 15 of the thousands of known MOFs for which enough experiments have been reported to allow strong conclusions to be drawn about the reproducibility of these measurements. Our results have immediate implications for the characterization of gas adsorption in porous materials but, more importantly, demonstrate an approach to assessing reproducibility that will be widely applicable in materials chemistry.

Continuum Model of Gas Uptake for Inhomogeneous Fluids

We describe a continuum model of gas uptake for inhomogeneous fluids (CMGIF) and use it to predict fluid adsorption in porous materials directly from gas-substrate interaction energies determined by first-principles calculations or accurate effective force fields. The method uses a perturbation approach to correct bulk fluid interactions for local inhomogeneities caused by gas–substrate interactions, and predicts local pressure and density of the adsorbed gas. The accuracy and limitations of the model are tested by comparison with the results of grand canonical Monte Carlo simulations of hydrogen uptake in metal–organic frameworks (MOFs). We show that the approach provides accurate predictions at room temperature and at low temperatures for less strongly interacting materials. The speed of the CMGIF method makes it a promising candidate for high-throughput materials discovery in connection with existing databases of nanoporous materials.

Accurate van der Waals force field for gas adsorption in porous materials.

An accurate van der Waals force field (VDW FF) was derived from highly precise quantum mechanical (QM) calculations. Small molecular clusters were used to explore van der Waals interactions between gas molecules and porous materials. The parameters of the accurate van der Waals force field were determined by QM calculations. To validate the force field, the prediction results from the VDW FF were compared with standard FFs, such as UFF, Dreiding, Pcff, and Compass. The results from the VDW FF were in excellent agreement with the experimental measurements. This force field can be applied to the prediction of the gas density (H2 , CO2 , C2 H4 , CH4 , N2 , O2 ) and adsorption performance inside porous materials, such as covalent organic frameworks (COFs), zeolites and metal organic frameworks (MOFs), consisting of H, B, N, C, O, S, Si, Al, Zn, Mg, Ni, and Co. This work provides a solid basis for studying gas adsorption in porous materials. © 2017 Wiley Periodicals, Inc.

Accurate Evaluation of the Dispersion Energy in the Simulation of Gas Adsorption into Porous Zeolites.

The force fields used to simulate the gas adsorption in porous materials are strongly dominated by the van der Waals (vdW) terms. Here we discuss the delicate problem to estimate these terms accurately, analyzing the effect of different models. To this end, we simulated the physisorption of CH4, CO2, and Ar into various Al-free microporous zeolites (ITQ-29, SSZ-13, and silicalite-1), comparing the theoretical results with accurate experimental isotherms. The vdW terms in the force fields were parametrized against the free gas densities and high-level quantum mechanical (QM) calculations, comparing different methods to evaluate the dispersion energies. In particular, MP2 and DFT with semiempirical corrections, with suitable basis sets, were chosen to approximate the best QM calculations; either Lennard-Jones or Morse expressions were used to include the vdW terms in the force fields. The comparison of the simulated and experimental isotherms revealed that a strong interplay exists between the definition of the dispersion energies and the functional form used in the force field; these results are fairly general and reproducible, at least for the systems considered here. On this basis, the reliability of different models can be discussed, and a recipe can be provided to obtain accurate simulated adsorption isotherms.

Investigation of load-dependent heat of adsorption of alkanes and alkenes on zeolites and activated carbon

To investigate the load-dependent heat of adsorption a sensor gas calorimeter was developed which allows the simultaneous measurement of adsorption capacity and heat of adsorption in porous materials. A commercially available volumetric measurement device was extended by a newly developed calorimetric measuring cell. Using this apparatus, the load-dependent heat of adsorption of alkanes and alkenes on the zeolites 13X-APG and HiSiv 3000 as well as on the activated carbon Norit R1 Extra was investigated. On all three adsorbents the heat of adsorption increases with chain length of the hydrocarbons. On HiSiv 3000 and Norit R1 Extra both load and heat of adsorption for all investigated alkanes and alkenes of the same chain length are very similar due to similar interactions with the adsorbent surface. Presumably dispersion interactions dominate adsorption in these systems. Contrary to these findings on 13X-APG higher loads and enthalpies of adsorption for alkenes than for alkanes occur. These higher heats of adsorption can be attributed to the energetically more attractive quadrupole-cation interactions between the double bond of alkenes and the cations of the zeolite.

Efficiently mapping structure-property relationships of gas adsorption in porous materials: application to Xe adsorption.

Designing better porous materials for gas storage or separations applications frequently leverages known structure-property relationships. Reliable structure-property relationships, however, only reveal themselves when adsorption data on many porous materials are aggregated and compared. Gathering enough data experimentally is prohibitively time consuming, and even approaches based on large-scale computer simulations face challenges. Brute force computational screening approaches that do not efficiently sample the space of porous materials may be ineffective when the number of possible materials is too large. Here we describe a general and efficient computational method for mapping structure-property spaces of porous materials that can be useful for adsorption related applications. We describe an algorithm that generates random porous "pseudomaterials", for which we calculate structural characteristics (e.g., surface area, pore size and void fraction) and also gas adsorption properties via molecular simulations. Here we chose to focus on void fraction and Xe adsorption at 1 bar, 5 bar, and 10 bar. The algorithm then identifies pseudomaterials with rare combinations of void fraction and Xe adsorption and mutates them to generate new pseudomaterials, thereby selectively adding data only to those parts of the structure-property map that are the least explored. Use of this method can help guide the design of new porous materials for gas storage and separations applications in the future.

Mechanism of CO2 adsorption on Mg/DOBDC with elevated CO2 loading

Understanding the nature of CO2 adsorption in porous materials is important to developing the next generation high performance adsorbents for CO2 capture. The mechanism of CO2 adsorption in a typical metal organic framework (MOF) material, named Mg/DOBDC (DOBDC=1,4-dioxido-2,5-benzenedicarboxylate), was investigated by experiments and theoretical calculations. Needle-shaped Mg/DOBDC crystals were synthesized and characterized. CO2 adsorption isotherm at ambient conditions on Mg/DOBDC was converted to obtain open metal site coverage by CO2 with pressure. Binding energies of CO2 on open metal site and organic linker site were calculated separately using density functional theory (DFT). Furthermore, step-by-step DFT calculations were performed by adding CO2 molecules into Mg/DOBDC pores one after another to mimic the CO2 adsorption process. The results show that CO2 adsorption energy is as high as −55.5kJ/mol on the open metal site (primary site) and about −27.1kJ/mol on the organic linkers (secondary site). As CO2 pressure increases, CO2 molecules occupy the open metal sites first, then organic linker site due to the difference in adsorption energy between these two sites. Correspondingly, charges transfer from adsorbed CO2 molecules to the framework continuously with increasing CO2 loading, which results in the variation of electrostatic environment. When six CO2 molecules are loaded in one single pore, each CO2 molecule interacts with the framework with same distance and angle.

Investigation of carbon dioxide adsorption by nitrogen-doped carbons synthesized from cubic MCM-48 mesoporous silica

Copyright © Korean Carbon Society http://carbonlett.org Carbon dioxide (CO2) is a component of the flue gas of power plants and automobile emissions. This gas is recognized as a primary greenhouse gas and is a presumed agent of climate change [1,2]. The drawbacks of the traditional MEA liquid method that is used for CO2 capture include the requirement for heavy equipment, and the toxic, flammable, corrosive, and volatile nature of the process [3]. Therefore, CO2 capture by means of adsorption in porous materials has received increasing attention because this method has proven to be superior than the conventional technologies in terms of the advantages associated with it. Compared to traditional processes, the convenient reversibility of adsorption on porous solid materials based on physisorption for the capture and release of CO2 makes this technique a greener and more cost-efficient method. To date, a variety of solid-based materials have been intensively studied for gas adsorption, especially CO2 capture, such as metal organic frameworks, covalent organic frameworks, zeolites, activated carbons, functionalized graphene, carbon molecular sieves, chemically modified mesoporous materials, etc [4-13]. Furthermore, the low concentration of CO2 in flue gas (ca. 15%) requires selective separation from the large volume of other component gases, mainly N2 [14]. Ideally, solid sorbents designed for CO2 capture should offer reduced energy consumption for regeneration, greater capture capacity, stability, selectivity, ease of handling, reduced environmental impact, etc. Currently, there is significant interest in the development of solid carbon adsorbents that are capable of selectively adsorbing CO2, because of their large surface area, porosity, abundance, cost efficiency, low density, fast adsorption kinetics, and high chemical and thermal stability [15-18]. Furthermore, these materials offer some advantages in terms of ease of handing, pore structure, and surface characteristics, as well as low-regeneration energy [19]. Therefore, carbon materials are currently considered attractive candidate sorbents for CO2 capture in the development of alternate clean and sustainable energy technologies. Based on these strengths, increasing efforts have recently been devoted to the synthesis of element-doped porous carbons that combine the high porosity and unique properties of doped carbon frameworks. The MCM-48 templated carbons have a high porosity without activation usually required to develop an accessible porous structure. Nitrogen doping has earned particular distinction because of the enhanced surface polarity, electrical conductivity, and electron-donor tendency conferred to the mesoporous carbons by nitrogen incorporation, which enables their application in CO2 capture, electric double-layer capacitors, fuel cells, catalysis, etc [20,21]. In the present study, we describe an alternate approach for the production of nitrogen-containing carbon materials with a cubic structure that facilitates CO2 diffusion and capture. Fig. 1a presents the low angle X-ray diffraction (XRD) pattern of MCM-48.The pattern exhibits several well-resolved peaks in the low-angle range of 2θ = 2°–6°, which can be indexed as the (211), (220), (420), and (332) diffraction peaks; this pattern corresponds to the cubic Ia3d space group [2,22]. In Fig. 1b high-angle XRD patterns, the synthesized carbon materials show two apparent peaks at around 2θ = 25° and 44°, which correspond to the (002) and (101) diffractions of the graphite structure, involving the hexagonal graphitic site and rhombohedral graphitic site, respectively [23]. Low-angle XRD patterns of the carbons synthesized with various amounts of pyrrole were acquired, as shown in Fig. DOI: http://dx.doi.org/ DOI:10.5714/CL.2016.18.062