A new molecular model for water adsorption on graphitized carbon black

Nguyen, Van Thuong; Do, D.D.; Nicholson, D.

doi:10.1016/j.carbon.2013.09.059

Cited by 43 publications

(29 citation statements)

References 40 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Thus it is concluded that water adsorbs on the functional groups at the junctions between adjacent graphene layers and argon adsorbs on the layers, and this is supported with our recent simulation work [20].…”

Section: Water Adsorption On Carbopack F and Hexsupporting

confidence: 74%

“…As the loading is increased water clusters are formed around the functional groups and grow in size because of the greater electrostatic interaction between water molecules than the dispersive water-graphene interaction [17]. This mechanism of adsorption was taken into account in the recent theories for water adsorption in porous carbon [12,18], and is also justified with molecular dynamics [19] and Monte Carlo simulations [20].…”

Section: A C C E P T E D Accepted Manuscriptmentioning

confidence: 95%

See 1 more Smart Citation

Scanning curves of water adsorption on graphitized thermal carbon black and ordered mesoporous carbon

Horikawa

Muguruma

et al. 2015

Carbon

Self Cite

View full text Add to dashboard Cite

Adsorption isotherms of water on porous carbons generally show large hysteresis loops whose origin is believed to be different from simple gases adsorption in mesoporous solids. In this paper, we discussed in details the behavior of water adsorption isotherms and their descending scanning curves for two carbons of different topologies, a highly graphitized thermal carbon black, Carbopack F, and a highly ordered mesoporous carbon, Hex. For both solids, very large hysteresis loops are observed, but their behaviors are different. For Carbopack F, the loop extends over a very wide range of pressure and the loop is larger when the descending is started from a higher loading; while for Hex, the hysteresis loop shows distinct steps, the number of which depends on the loading where the descending starts. By carefully analyzing the scanning curves from different loadings, we established the mechanism of water adsorption in Hex as a sequence of three steps: (1) water molecules adsorb on functional groups located at the junctions between adjacent basal planes of graphene layers, (2) growth of water clusters around the functional groups, and (3) bridging of adjacent clusters to form larger clusters, followed by a complete filling of mesopores.

show abstract

Section: Water Adsorption On Carbopack F and Hexsupporting

confidence: 74%

Section: A C C E P T E D Accepted Manuscriptmentioning

confidence: 95%

Scanning curves of water adsorption on graphitized thermal carbon black and ordered mesoporous carbon

Horikawa

Muguruma

et al. 2015

Carbon

Self Cite

View full text Add to dashboard Cite

show abstract

“…Adsorption of water on carbon surfaces has been intensively studied [2,3], these materials presenting interesting environmental applications as adsorbents in aqueous solutions. In the graphitic form, carbon should not have strong interactions with water, since weak forces are involved in these interactions, but several simulations proved that water can be strongly adsorbed at low relative pressures by carbon adsorbents due to the potential overlap in small pores [4,5].…”

Section: Introductionmentioning

confidence: 99%

Thermophysical investigations of exfoliated graphite nanoplatelets and active carbon in binary aqueous environments at different temperatures

2014

View full text Add to dashboard Cite

Thermophysical investigations in binary liquid mixtures are important for many technological and environmental applications of exfoliated graphite nanostructures. The densities, speeds of sound, and refractive indices for the binary liquid mixture environments of water ? exfoliated graphite nanoplatelets, and water ? activated carbon have been measured versus composition, at different temperatures, at atmospheric pressure. The thermophysical properties such as the acoustic impedance, isentropic compressibility, specific refraction, space-filling factor, and relaxation strength have been evaluated over the composition range up to 100 kg m -3 , based on the experimental data. The absolute average percentage deviations of the calculated thermophysical properties in both systems were computed. The obtained results are discussed and interpreted in terms of molecular interactions and structural changes of these carbon-based nanomaterials.

show abstract

“…This also allows us to elucidate the mechanism of water adsorption: water molecules mainly cluster around the functional group, rather than on the basal plane, and once water has been adsorbed on the functional group, this complex acts as a nucleus for more water molecules to grow around it and form a larger cluster because the water-water intermolecular interaction is much greater than that between water and the basal plane. More details can be found in [48]. …”

mentioning

confidence: 99%

Novel approach to the characterization of the pore structure and surface chemistry of porous carbon with Ar, N2, H2O and CH3OH adsorption

Fan

Nguyen

Zeng

et al. 2015

Microporous and Mesoporous Materials

Self Cite

View full text Add to dashboard Cite

Characterization of porous carbon for its pore size distribution is traditionally carried out with simple pore models of well-defined geometry (slit or cylinder) with both ends opened to the gas surroundings. These idealised models do not adequately describe the inherently complex structure of porous carbons. An improved model should be sufficiently simple, not only for characterization, but also for the design of separation and purification processes. The following factors should be included: (1) energetic variation along the pore axis due to constrictions or strong energy sites, (2) connectivity between adjacent pores and (3) the presence of functional groups. In this work, we report results from computer simulations, using argon and nitrogen as non polar or weakly polar adsorbates and water and methanol as examples of associating fluids. The new model is able to produce all hysteresis loops classified by the IUPAC as well as loop types reported earlier by de Boer [1], Experimental isotherms are commonly measured at 77K and 87K (nitrogen and argon boiling points, respectively), but in recent years cryostats have become increasingly available in characterization laboratories and our simulations show that by measuring isotherms at different temperatures new insights about the porous structure can be gained from the variation of the hysteresis loop with respect to temperature which may change, for example, from a single-loop to a double-loop via a fused-loop as the temperature is varied.

show abstract

A new molecular model for water adsorption on graphitized carbon black

Cited by 43 publications

References 40 publications

Scanning curves of water adsorption on graphitized thermal carbon black and ordered mesoporous carbon

Scanning curves of water adsorption on graphitized thermal carbon black and ordered mesoporous carbon

Thermophysical investigations of exfoliated graphite nanoplatelets and active carbon in binary aqueous environments at different temperatures

Novel approach to the characterization of the pore structure and surface chemistry of porous carbon with Ar, N2, H2O and CH3OH adsorption

Contact Info

Product

Resources

About