Chemistry, Physics and Technology of Surface

ISSN 2518-1238 (Online), ISSN 2079-1704 (Print)

The aim of this study was to analyze various theoretical models (clusters, systems with periodic boundary conditions) and methods, which could be applied to investigate the adsorption phenomena and for better interpretation of the experimental data. The density functional theory (DFT) and semiempirical (PM7) methods were used to model the adsorption phenomena at a surface of fumed nanooxides, silica gels, activated carbons, etc. The main idea is that appropriate theoretical analysis allows a deeper insight into interfacial phenomena related to the structure & properties of the adsorption layers vs. the textural and other characteristics of adsorbents. Comparison of the theoretically calculated characteristics with experimental ones can allow more accurate interpretation of the effects observed in various experiments on the adsorption phenomena. It was established that polarization of nonpolar and polar molecules adsorbed onto a polar surface and charge (& proton) transfer play an important role, as well as confined space effects. It enhances the interaction energy of adsorbed molecules bound to a solid surface and affects the surface orientation of adsorbed molecules, as well the behavior of the adsorption layer vs. temperature, pressure or concentration, as well other conditions. Surface hydrophobization reduces the interaction energy for both polar and nonpolar adsorbates. Adsorbates clusterization reduces the average energy of interaction of the adsorption layer with a surface per a molecule. The charge transfer is observed for both polar and nonpolar molecules interacting with polar surface functionalities. The mostly strong interfacial effects changing the behavior of the adsorption layer are observed upon proton transfer to the adsorbed molecules or vice versa. Variation in orientation of adsorbed molecules results in overestimation of the specific surface area estimated using a fixed value of surface area occupied by a probe molecule (e.g. 0.162 nm² for N₂).

1. Gregg S.J., Sing K.S.W. Adsorption, Surface Area and Porosity. 2nd ed. (London: Academic Press, 1982).

2. Adamson A.W., Gast A.P. Physical Chemistry of Surface. 6th ed. (New York: Wiley, 1997).

3. Iler R.K. The Chemistry of Silica. (Chichester: Wiley, 1979).

4. Legrand A.P. The Surface Properties of Silicas. (New York: Wiley, 1998).

5. Bergna H.E., Roberts W.O. Colloidal Silica: Fundamentals and Applications. (Boca Raton: CRC Press, 2006).

6. Ghosh S.K. Functional Coatings. (Weinheim: Wiley-VCH Verlag GmbH, 2006).

7. Tapia O., Bertrán J. Solvent Effects and Chemical Reactivity. (New York: Kluwer Academic Publishers, 2000).

8. Somasundaran P. Encyclopedia of Surface and Colloid Science. Third Edition. (Boca Raton: CRC Press, 2015). https://doi.org/10.1081/E-ESCS3

9. Henderson M.A. The interaction of water with solid surfaces: fundamental aspects revisited. Surf. Sci. Rep. 2002. 46(1-8): 1. https://doi.org/10.1016/S0167-5729(01)00020-6

10. Birdi K.S. Handbook of Surface and Colloid Chemistry. Third edition. (Boca Raton: CRC Press, 2009). https://doi.org/10.1201/9781420007206

11. Al-Abadleh H.A., Grassian V.H. Oxide surfaces as environmental interfaces. Surf. Sci. Rep. 2003. 52(3-4): 63. https://doi.org/10.1016/j.surfrep.2003.09.001

12. Chandler D. Interfaces and the driving force of hydrophobic assembly. Nature. 2005. 437: 640. https://doi.org/10.1038/nature04162

13. Gun'ko V.M., Turov V.V. Nuclear Magnetic Resonance Studies of Interfacial Phenomena. (Boca Raton: CRC Press, 2013). https://doi.org/10.1201/b14202

14. Dykstra C.E., Frenking G., Kim K.S., Scuseria G.E. Theory and Applications of Computational Chemistry, the First Forty Years. (Amsterdam: Elsevier, 2005).

15. Canuto S. Solvation Effects on Molecules and Biomolecules. Computational Methods and Applications. (Dordrecht: Springer, 2008). https://doi.org/10.1007/978-1-4020-8270-2

16. Schleyer P.v.R. Encyclopedia of Computational Chemistry. (New York: John Wiley & Sons, 1998).

17. Cramer C.J. Essentials of computational chemistry: theories and models. Second ed. (Chichester, UK: John Wiley & Sons, Ltd, 2008).

18. Yang K., Zheng J., Zhao Y., Truhlar D.G. Tests of the RPBE, revPBE, τ-HCTHhyb, ωB97X-D, and MOHLYP density functional approximations and 29 others against representative databases for diverse bond energies and barrier heights in catalysis. J. Chem. Phys. 2010. 132(16): 164117. https://doi.org/10.1063/1.3382342

19. Frisch M.J., Trucks G.W., Cheeseman J.R., Scalmani G., Caricato M., Hratchian H.P., Li X., Barone V., Bloino J., Zheng G. Gaussian 09, Version D.01. Gaussian Inc. Wallingford CT 2013.

20. Schmidt M.W., Baldridge K.K., Boatz J.A., Elbert S.T., Gordon M.S., Jensen J.H., Koseki S., Matsunaga N., Nguyen K.A., Su S., Windus T.L., Dupuis M., Montgomery J.A. Jr. General atomic and molecular electronic structure system. J. Comput. Chem. 1993. 14(11): 1347. https://doi.org/10.1002/jcc.540141112

21. Marenich A.V., Cramer C.J., Truhlar D.G. Universal solvation model based on solute electron density and on a continuum model of the solvent defined by the bulk dielectric constant and atomic surface tensions. J. Phys. Chem. B. 2009. 113(18): 6378. https://doi.org/10.1021/jp810292n

22. Marenich A.V., Cramer C.J., Truhlar D.G. Performance of SM6, SM8, and SMD on the SAMPL1 test set for the prediction of small-molecule solvation free energies. J. Phys. Chem. B. 2009. 113(14): 4538. https://doi.org/10.1021/jp809094y

23. Stewart J.J.P. MOPAC2016. Stewart Computational Chemistry. 2019. http://openmopac.net

24. Dennington R., Keith T., Millam J. GaussView, Version 5.09. Semichem Inc., Shawnee Mission KS, 2013.

25. Zhurko G.A., Zhurko D.A. Chemcraft (version 1.8). 2019. http://www.chemcraftprog.com

26. Hanwell M.D., Curtis D.E., Lonie D.C., Vandermeersch T., Zurek E., Hutchison G.R. Avogadro: an advanced semantic chemical editor, visualization, and analysis platform. J. Chem. Inf. 2012. 4(17): 1. https://doi.org/10.1186/1758-2946-4-17

27. Gun'ko V.M. Composite materials: textural characteristics. Appl. Surf. Sci. 2014. 307: 444. https://doi.org/10.1016/j.apsusc.2014.04.055

28. Gun'ko V.M., Turov V.V., Gorbyk P.P. Water at the Interfaces. (Kyiv: Naukova Dumka, 2009). [in Russian].

29. Gun'ko V.M., Turov V.V., Zarko V.I., Goncharuk O.V., Pahklov E.M., Skubiszewska-Zięba J., Blitz J.P. Interfacial phenomena at a surface of individual and complex fumed nanooxides. Adv. Colloid Interface Sci. 2016. 235: 108. https://doi.org/10.1016/j.cis.2016.06.003

30. Gun'ko V.M. Interfacial phenomena: effects of confined space and structure of adsorbents on the behavior of polar and nonpolar adsorbates at low temperatures. Current Physical Chemistry. 2015. 5(2): 137. https://doi.org/10.2174/187794680502160111093413

31. Gun'ko V.M. Modeling of interfacial behavior of water and organics. J. Theor. Comput. Chem. 2013. 12(07): 1350059. https://doi.org/10.1142/S0219633613500594

32. Gun'ko V.M., Pakhlov E.M., Goncharuk O.V., Andriyko L.S., Nychiporuk Yu.M., Balakin D.Yu., Sternik D., Derylo-Marczewska A. Nanosilica modified by polydimethylsiloxane depolymerized and chemically bound to nanoparticles or physically bound to unmodified or modified surfaces: Structure and interfacial phenomena. J. Colloid Interface Sci. 2018. 529: 273. https://doi.org/10.1016/j.jcis.2018.06.019

33. Gun'ko V.M., Turov V.V., Pakhlov E.M., Krupska T.V., Borysenko M.V., Kartel M.T., Charmas B. Water interactions with hydrophobic versus hydrophilic nanosilica. Langmuir. 2018. 34(40): 12145. https://doi.org/10.1021/acs.langmuir.8b03110

34. Gun'ko V.M., Turov V.V., Krupska T.V., Pakhlov E.M. Behavior of water and methane bound to hydrophilic and hydrophobic nanosilicas and their mixture. Chem. Phys. Lett. 2017. 690: 25. https://doi.org/10.1016/j.cplett.2017.10.039

35. Turov V.V., Gun'ko V.M., Pakhlov E.M., Krupska T.V., Tsapko M.D., Charmas B., Kartel M.T. Influence of hydrophobic nanosilica and hydrophobic medium on water bound in hydrophilic components of complex systems. Colloids Surf. A. 2018. 552: 39. https://doi.org/10.1016/j.colsurfa.2018.05.017

36. Gun'ko V.M., Pakhlov E.M., Goncharuk O.V., Andriyko L.S., Marynin A.I., Ukrainets A.I., Charmas B., Skubiszewska-Zięba J., Blitz J.P. Influence of hydrophobization of fumed oxides on interactions with polar and nonpolar adsorbates. Appl. Surf. Sci. 2017. 423: 855. https://doi.org/10.1016/j.apsusc.2017.06.207

37. Gun'ko V.M., Turov V.V., Pakhlov E.M., Krupska T.V., Charmas B. Effect of water content on the characteristics of hydro-compacted nanosilica. Appl. Surf. Sci. 2018. 459: 171. https://doi.org/10.1016/j.apsusc.2018.07.213