Localization of Hydrogen in Porous Space of Activated Carbon

Authors

  • V. V. Turov Chuiko Institute of Surface Chemistry of National Academy of Sciences of Ukraine
  • V. M. Gun'ko Chuiko Institute of Surface Chemistry of National Academy of Sciences of Ukraine
  • O. P. Kozynchenko MAST Carbon International Ltd
  • S. P. Tennison MAST Carbon International Ltd
  • S. V. Mikhalovski University of Brighton

Abstract

Adsorption of hydrogen on activated carbons (ACs) was studied in quasi-isobaric conditions (P = 1.1·105 Pa) using low-temperature 1H NMR spectroscopy. The ACs were prepared by carbonization of porous phenol-formaldehyde resin beads with subsequent activation by CO2 with the burn-off degree of 86% (AC-86) and 47% (AC-47). It has been shown that the hydrogen adsorption increases with increasing concentration of water pre-adsorbed in pores of AC-86 (specific surface area 3463 cm2/g). In the case of the water adsorption in the amounts of 40 mg/g, the hydrogen adsorption reaches 1.4 mg/g at T = 200 K. The adsorbed hydrogen was localized in the slit-shaped pores where the zero shielding effect of the surface was shown. The results obtained are explained by the existence of slit-shaped pores with three minima in the cross section curve of the potential energy of adsorption, and two of them are localized near the pore walls (where the shielding effect of the surface is larger) and the third one is in the middle of pores (where the shielding effect is close to zero). All adsorbates with exception of hydrogen (water, saturated hydrocarbons) are localized mainly at the pore walls. A part of water can be moved to the middle of pores with decreasing temperature that reduces the screening effect of the surface. Adsorbed hydrogen is localized in the middle space of the pores with the presence of co-adsorbates or in the narrowest pores where co-adsorbates cannot be adsorbed.

References

Dobrovolsky V.D., Ershova O.G., Solonin Yu.M. et al. A study of the hydrogen sorption properties, thermal stability and the character of the chemical bonds of Ho and Lu Me–H hydrides through the use of thermodesorption and X-ray absorption spectroscopy // J. Alloys Compd. – 2010. – V. 490, N 1–2. – P. 68–73.

Demircan A. Experimental and theoretical analysis of hydrogen absorption in LaNi5–H2 reactors // Int. J. Hydrogen Energy. – 2005. – V. 30, N 1–2. – P. 1437–1446.

Dhaou H., Souahlia A., Mellouli S. et.al. Experimental study of a metal hydride vessel based on a finned spiral heat exchanger // Int. J. Hydrogen Energy. – 2010. – V. 35, N 4. – P. 1674–1680.

Елецкий А.В. Сорбционные свойства углеродных наноструктур // Усп. физ. наук. – 2004. – Т. 174, № 11. – С. 1191–1231.

Нечаев Ю.С. О природе, кинетике и предельных значениях сорбции водорода углеродными наноструктурами // Усп. физ. наук. – 2006. – Т. 176, № 6. – С. 581–610.

Нечаев Ю.С., Алексеев О.К. Методологический, прикладной и термодинамический аспекты сорбции водорода графитом и родственными углеродными наноструктурами // Усп. химии. – 2004. – Т. 73, № 12. – С. 1309–1337.

Huang C-C., ChenH-M., Chen C-H. Hydrogen adsorption on modified activated carbon // Int. J. Hydrogen Energy. – 2010. – V. 35, N 7. – P. 2777–2780.

Rzepka M., Lamp P., de la Casa-Lillo M.A. Physisorption of hydrogen on microporous carbon and carbon nanotubes // J. Phys. Chem. B. – 1998. – V. 102, N 52. – P. 10894–10904.

Texier-Mandoki N., Dentzer J., Piquero T. et al. Hydrogen storage in activated carbon materials: role of the nanoporous texture // Carbon. – 2004. – V. 42, N 12–13. – P. 2744–2751.

Saha D., Deng S. Enhanced hydrogen adsorption in ordered mesoporous carbon through clathrate formation // Int. J. Hydrogen Energy. – 2009. – V. 34, N 20. – P. 8583–8588.

Фенелонов В.Б. Пористый углерод. – Новосибирск: ИК СО РАН, 1995. – 518 с.

Tabony J., White J.W., Delacheume J.C., Coulon M. Nuclear Magnetic Resonance Studies of the Magnetic and Orientation of Benzene Adsorption upon Graphite // Surf. Sci. Lett. – 1980. – V. 95, N 1–2. – P. 282–288.

Turov V.V., Leboda R. 1H NMR spectroscopy of adsorbed molecules and free surface energy of carbon adsorbents // Phys. Chem. Carbon. – 2000. – V. 27. – P. 67–124.

Turov V.V., Leboda R. 1H NMR chemical shifts of adsorbed molecules on the carbon surface // Adsorpt. Sci. Technol. – 1998. – V. 16, N 10. – P. 837–855.

Pat. 7842736 United States, Int. Cl. C08G8/04 Porous carbons / Tennison S.R., Kozynchenko O.P., Strelko V.V., Blackburn A.J. – Appl. No. 11/786072, Filed 10.04.2007, Publ. 30.11.2010. – 26 p

Gun’ko V.M., Turov V.V., Bogatyrev V.M. et al. Unusual properties of water at hydrophilic/hydrophobic Interfaces // Adv. Colloid Interface Sci. − 2005 − V. 118, N 1–3. − P. 125–172.

Гунько В.М., Туров В.В., Горбик П.П. Вода на межфазной границе. – Киев: Наукова думка, 2009. – 694 с.

Turov V.V., Leboda R. Application of 1H NMR Spectroscopy Method for Determination of Characteristics of Thin Layers of Water Adsorbed on the Surface of Dispersed and Porous Adsorbens // Adv. Colloid Interface Sci. – 1999. – V. 79, N 2–3. – P. 173–211.

Туров В.В., Гунько В.М., Хоменко К.Н. и др. Адсорбция водорода на силикалите в присутствии воды и бензола. – ЖФХ. – 2010. – т. 84. – с. 76–81.

Туров В.В., Гунько В.М., Пєтін А.Ю. та ін. Спільна адсорбція водню та води в наностуктурованих адсорбентах за даними 1Н ЯМР спектроскопії // Наносистеми, наноматеріали та нанотехнології. – 2010. – Т. 8, № 1. – С. 153–175.

Dubinin M.M. Generalization of the theory of volume filling of microporous to nonhomogeneous microporous structures // Carbon. – 1985. – V. 23, N. 4. – P. 373–380.

Petrov O.V., Furo I. NMR cryoporometry: Principles, application and potential // Prog. Nucl. Magn. Reson. Spectrosc. – 2009. – V. 54, N 2. – P. 97–122.

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(1)
Turov, V. V.; Gun’ko, V. M.; Kozynchenko, O. P.; Tennison, S. P.; Mikhalovski, S. V. Localization of Hydrogen in Porous Space of Activated Carbon. Him. Fiz. Tehnol. Poverhni 2011, 2, 23-33.

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Vol. 2 No. 1 (2011): Chemistry, Physics and Technology of Surface / Himia, Fizika ta Tehnologia Poverhni

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