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)

• 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

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Identifiers

DOI

10.12693/APhysPolA.113.1517