Molecular Modeling of Porous Carbons Using the Hybrid Reverse Monte Carlo Method

Jain, S. K.; Pellenq, Roland J.‐M.; Pikunic, Jorge; Gubbins, Keith E.

doi:10.1021/la053402z

Cited by 172 publications

(174 citation statements)

References 32 publications

Supporting

Mentioning

166

Contrasting

Order By: Relevance

“…This is key, e.g., to help settle arguments such as the large variations reported in water fluxes through CNT--based RO membranes (discussed in section 2). Gubbins and coworkers developed advanced algorithms for reproducing the sub nm--level features of carbon adsorbents (177,178). Similar approaches should be attempted to replicate the physical properties of GO stacks used in RO membranes, to better understand how processing conditions determine the performance of such devices.…”

Section: Frontiers Of Simulation Studiesmentioning

confidence: 99%

The Carbon-Water Interface: Modeling Challenges and Opportunities for the Water-Energy Nexus

Striolo

Michaelides

Joly

2016

Annu. Rev. Chem. Biomol. Eng.

View full text Add to dashboard Cite

Providing clean water and sufficient affordable energy to all without compromising the environment are key priorities of the scientific community. Many recent studies have focused on carbon--based devices in the hope of addressing these grand challenges, justifying and motivating detailed studies of water in contact with carbonaceous materials. Such studies are becoming increasingly important because of the miniaturization of newly proposed devices, with ubiquitous nano--pores, large surface--to--volume ratio, and many, perhaps most of the water molecules at contact with a carbon--based surface. In this brief review we discuss some recent advances obtained by simulations and experiments in the development of carbon--based materials for applications in water desalination. We suggest possible ways forward, with particular emphasis on the synergistic combination of experiments and simulations, with simulations now sometimes offering sufficient accuracy to provide fundamental insights. We also point the interested reader to recent works that complement our short summary on the state of the art of this important and fascinating field. 2 Introduction: the importance of reverse osmosis in water desalinationThe scientific community is facing the challenge of providing technological solutions for the water--energy nexus while preserving the environment. Carbon--based devices have been developed both for desalinating water and for storing energy. Such devices are characterized by vast carbon--water interfaces, due to the ubiquity of nano--pores. It is indeed possible that many, perhaps most water molecules within such devices come in contact with the carbon surface. Hence, a detailed understanding of water--carbon interfaces is necessary to ensure progress. Here, we review some recent advances obtained by atomistic simulations and experiments on this field. Traditional water desalination approaches such as multi--flash distillations are widely used, but require large amounts of energy. As such, they are not sustainable in the long run. Reverse osmosis (RO) has become the technology of choice for most new installations. Two innovations are considered to be responsible for the wide application of RO. The first was the introduction of thin film composite membranes; the other was the implementation of energy recovery devices that re--use part of the energy present in pressurized brine (i.e., pressure exchangers and efficient pumps) (1, 2). Although RO is mature and reliable, it remains energy intensive (3--5). At its core are membranes permeable to water and impermeable to salt. The state--of--the art membranes, based on polyamide thin film composites, degrade in the presence of chlorine (which makes disinfection difficult) and are prone to fouling (6). Many believe that 'in order for desalination to live up to the water challenges of the 21 st century a step--change is needed in RO membrane technology' (7). Although high mechanical strength as well as resistance to degradation and fouling are prerequisites to practical appli...

show abstract

Section: Frontiers Of Simulation Studiesmentioning

confidence: 99%

The Carbon-Water Interface: Modeling Challenges and Opportunities for the Water-Energy Nexus

Striolo

Michaelides

Joly

2016

Annu. Rev. Chem. Biomol. Eng.

View full text Add to dashboard Cite

show abstract

“…Further applications of the CRMC algorithm by Walters et al [12], Thomson and Gubbins [13] and Pikunic et al [14,15] yielded some success, while still demonstrating the presence of unphysical configurations in constructed models of disordered carbon, which appeared to be an intrinsic byproduct of the RMC algorithm [8,9]. The major improvement in this regard was the development of the Hybrid Reverse Monte Carlo (HRMC) technique [9,[16][17][18]. The new algorithm performs conventional CRMC simulation, while simultaneously implementing an energy minimization scheme using reactive force fields.…”

Section: ୀଵmentioning

confidence: 99%

Hybrid Reverse Monte Carlo simulation of amorphous carbon: Distinguishing between competing structures obtained using different modeling protocols

Farmahini

Bhatia

2015

Carbon

View full text Add to dashboard Cite

Please cite this article as: Farmahini, A.H., Bhatia, S.K., Hybrid reverse monte carlo simulation of amorphous carbon: Distinguishing between competing structures obtained using different modelling protocols, Carbon (2014), doi: http://dx.doi.org/10.1016/j.carbon. 2014.11.013 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ABSTRACTWe explore different multi-stage and multi-constraint modelling strategies using the Hybrid Reverse Monte Carlo (HRMC) technique to develop realistic models for the amorphous structure of silicon carbide derived-carbon, and investigate the effect of modelling parameters on the development of nano-structural features of the constructed models. It is shown that application of long simulations with slow thermal quench rate is essential for modelling of amorphous structures. Nevertheless, very slow quenching rates are shown to lead to the formation of configurations with large fraction of sp 2 carbon, lacking the level of disorder required to match structure-related experimental data. The predicted gas adsorption isotherms are very sensitive to the pore size distribution (PSD), thus the final structure must reasonably reproduce the total pore volume and pore size distribution of the experimental sample. The frequently-observed strong first peak of the DFT-based PSD obtained from argon adsorption is shown to be an artifact of argon inaccessibility. Pore accessibility analysis of the constructed models, as well as MD simulations of gas transport demonstrate that the HRMC constructed structures contain short-range structural anisotropy, however the models are successful in capturing the long range internal energy barriers of amorphous carbon for methane.

show abstract

“…The second material we consider is CS1000, a molecular reconstruction of a saccharose-based heat-activated carbon (CS) obtained by Hybrid Reverse Monte Carlo method (Jain et al 2006). CS1000 is a glassy nanoporous material composed of a highly cross-linked polymeric network (Fig.…”

Section: Simulation Of Nanoporous Polymermentioning

confidence: 99%

Capturing material toughness by molecular simulation: accounting for large yielding effects and limits

et al. 2015

View full text Add to dashboard Cite

The inherent computational cost of molecular simulations limits their use to the study of nanometric systems with potentially strong size effects. In the case of fracture mechanics, size effects due to yielding at the crack tip can affect strongly the mechanical response of small systems. In this paper we consider two examples: a silica crystal for which yielding is limited to a few atoms at the crack tip, and a nanoporous polymer for which the process zone is about one order of magnitude larger. We perform molecular simulations of fracture of those materials and investigate in particular the system and crack size effects. The simulated systems are periodic with an initial crack. Quasi-static loading is achieved by increasing the system size in the direction orthogonal to the crack while maintaining a constant temperature. As expected, the behaviors of the two materials are significantly different. We show that the behavior of the silica crystal is reasonably well described by the classical framework of linear elastic fracture mechanics (LEFM). Therefore, one can easily upscale engineering fracture properties from molecular simulation results. In contrast, LEFM fails capturing the behavior of the polymer and we propose an alternative analysis based on cohesive crack zone models. We show that with a linear decreasing cohesive law, this alternative approach captures well the behavior of the polymer. Using this cohesive law, one can anticipate the mechanical behavior at larger scale and assess engineering fracture properties. Thus, despite the large yielding of the polymer at the scale of the molecular simulation, the cohesive zone analysis offers a proper upscaling methodology.

show abstract

Molecular Modeling of Porous Carbons Using the Hybrid Reverse Monte Carlo Method

Cited by 172 publications

References 32 publications

The Carbon-Water Interface: Modeling Challenges and Opportunities for the Water-Energy Nexus

The Carbon-Water Interface: Modeling Challenges and Opportunities for the Water-Energy Nexus

Hybrid Reverse Monte Carlo simulation of amorphous carbon: Distinguishing between competing structures obtained using different modeling protocols

Capturing material toughness by molecular simulation: accounting for large yielding effects and limits

Contact Info

Product

Resources

About