Nanopores in Silica Aerogels

• Authors: O. Šauša , M. Iskrová , V. Majerník , J. Krištiak , K. Jesenák , M. Vargová
• Languages of publication: EN

Abstracts

EN

The size of nanopores in thermally treated samples of silica aerogels was determined by ortho-positronium lifetime measurements at room temperature. The annealing of samples in the temperature region of 300-800°C does not make substantial changes in pore size felt by positronium. The annealing at higher temperatures from an interval of 800-1050°C causes shrinkage of the samples reducing the pore size to 1-15 nm. The macropores vanish at temperature treatment at 1000°C and the positron annihilation is not affected by oxygen from air.

Keywords

EN

78.70.Bj

Discipline

• 78.70.Bj: Positron annihilation(for positron states, see 71.60.+z in electronic structure of bulk materials; for positronium chemistry, see 82.30.Gg in physical chemistry and chemical physics)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2008
• Volume: 113
• Issue: 5
• Pages: 1517-1522

Dates

published

2008-05

received

2007-09-03

Contributors

author

O. Šauša

• Institute of Physics of SAS, Dúbravská cesta 9, 854 11 Bratislava, Slovakia

author

M. Iskrová

• Institute of Physics of SAS, Dúbravská cesta 9, 854 11 Bratislava, Slovakia

author

V. Majerník

• Institute of Physics of SAS, Dúbravská cesta 9, 854 11 Bratislava, Slovakia

author

J. Krištiak

• Institute of Physics of SAS, Dúbravská cesta 9, 854 11 Bratislava, Slovakia

author

K. Jesenák

• Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská Dolina CH-2, 842 15 Bratislava, Slovakia

author

M. Vargová

• Department of Inorganic Chemistry, Faculty of Natural Sciences, Comenius University in Bratislava, Mlynská Dolina CH-2, 842 15 Bratislava, Slovakia

References

• 1. S.J. Tao, J. Chem. Phys. 56, 5499 (1972)
• 2. M. Eldrup, D. Lightbody, J.N. Sherwood, Chem. Phys. 63, 51 (1981)
• 3. H. Nakanishi, Y.C. Jean, Positron and Positronium Chemistry, Elsevier, Amsterdam 1988
• 4. K. Ito, H. Nakanishi, Y. Ujihira, J. Phys. Chem. B 103, 4555 (1999)
• 5. T.L. Dull, W.E. Frieze, D.W. Gidley, J.N. Sun, A.F. Yee, J. Phys. Chem. B 105, 4657 (2001)
• 6. D.W. Gidley, K.A. Marko, A. Rich, Phys. Rev. Lett. 36, 395 (1976)
• 7. T. Goworek, K. Ciesielski, B. Jasinska, J. Wawryszczuk, Chem. Phys. Lett. 272, 91 (1997)
• 8. D.W. Gidley, W.E. Frieze, T.L. Dull, A.F. Yee, E.T. Ryan, H.M. Ho, Phys. Rev. B 60, R5157 (1999)
• 9. Y.C. Jean, H. Shi, J. Non-Cryst. Solids 172-174, 806 (1994)
• 10. G. Consolati, J. Chem. Phys. 117, 7279 (2002)
• 11. M.V. Félix, R.A. Rodríguez-Rojas, J. Castaneda-Contreras, R. Morones, V.M. Castano, Opt. Mater. 27, 1291 (2005)
• 12. R. Zaleski, Positronium Lifetime vs. Temperature and Free Volume Size Tables. Pick-Off Model Calculations, Institute of Physics, Maria Curie-Skłodowska University, Lublin 2002
• 13. I.R. Boyko, M.A. Ignatenko, K. Esenak, L. Kuchta, J. Ružička, V. Fainor, Nucl. Instrum. Methods Phys. Res. A 363, 568 (1995)
• 14. J. Kansy, Nucl. Instr. Methods Phys. Res. A 374, 235 (1996)
• 15. K. Cieselski, A.L. Dawidowicz, T. Goworek, B. Jasinska, J. Wawryszczuk, Chem. Phys. Lett. 289, 41 (1998)
• 16. C. Hugenschmidt, U. Holzwarth, M. Jansen, S. Kohn, K. Maier, J. Non-Cryst. Solids 217, 72 (1997)
• 17. B. Himmel, Th. Gerber, H. Burger, G. Holzhutter, A. Olbertz, J. Non-Cryst. Solids 186, 149 (1995)

Identifiers

DOI

10.12693/APhysPolA.113.1517