Positron Porosimetry Studies of Template Removal from As-Synthesized MCM-41 Silica

• Authors: R. Zaleski , J. Wawryszczuk
• Languages of publication: EN

Abstracts

EN

The course of template removal from MCM-41 pores was investigated by positron annihilation lifetime spectroscopy. Two methods of removal were the object of interest: a decarbonisation after standard calcination procedure and a novel procedure - pyrolysis in vacuum. The shapes of positron lifetime spectra of decarbonised sample are determined by positronium quenching caused by presence of carbon deposit on the surface. Positron annihilation lifetime spectroscopy allows also monitoring the evolution of empty space inside pores. During pyrolysis no conductive carbon is produced, so consecutive stages of template material transformation are easy to observe. In the case of pyrolysis the effect of pore emptying is obtained at temperature 500 K, lower comparing to calcination and decarbonisation (820 K).

Keywords

EN

78.70.Bj; 36.10.Dr; 61.43.Gt; 81.07.-b

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)
• 81.07.-b: Nanoscale materials and structures: fabrication and characterization(for structure of nanoscale materials, see 61.46.-w; for nanostructured materials in electrochemistry, see 82.45.Yz; see also 62.23.-c Structural classes of nanoscale systems in mechanical properties of condensed matter)
• 61.43.Gt: Powders, porous materials
• 36.10.Dr: Positronium(see also 82.30.Gg Positronium chemistry)

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2008
• Volume: 113
• Issue: 5
• Pages: 1543-1550

Dates

published

2008-05

received

2007-09-03

Contributors

author

R. Zaleski

• Institute of Physics, Maria Curie-Skłodowska University, pl. Marii Curie-Skłodowskiej 1, 20-031 Lublin, Poland

author

J. Wawryszczuk

• Institute of Physics, Maria Curie-Skłodowska University, pl. Marii Curie-Skłodowskiej 1, 20-031 Lublin, Poland

References

• 1. D. Lightbody, J.N. Sherwood, M. Eldrup, Chem. Phys. 93, 475 (1985)
• 2. T. Goworek, K. Ciesielski, B. Jasińska, J. Wawryszczuk, Chem. Phys. Lett. 272, 91 (1997)
• 3. C.T. Kresge, M.E. Leonowicz, W.J. Roth, J.C. Vartuli, J.S. Beck, Nature 359, 710 (1992)
• 4. R. Zaleski, Acta. Phys. Pol. A 110, 729 (2006)
• 5. A. Shukla, M. Peter, L. Hoffman, Nucl. Instrum. Methods Phys. Res. A 335, 310 (1993)
• 6. M. Grűn, K.K. Unger, A. Matsumoto, K. Tsutsumi, in: Characterization of Porous Solids IV, Eds. B. McEnaney, T.J. Mays, J. Rouquerol, F. Rodríguez- -Reinoso, K.S.W. Sing, K.K. Unger, The Royal Society of Chemistry, London 1997, p. 81
• 7. J. Wawryszczuk, J. Goworek, R. Zaleski, T. Goworek, Langmuir 19, 2599 (2003)
• 8. M. Eldrup, N.J. Pedersen, J.N. Sherwood, Phys. Rev. Lett. 43, 1407 (1979)
• 9. R. Zaleski, J. Wawryszczuk, J. Goworek, A. Borówka, T. Goworek, J. Colloid Interface Sci. 262, 466 (2003)
• 10. F. Kleitz, W. Schmidt, F. Schűth, Microporous Mesoporous Mater. 44-45, 95 (2001)
• 11. B. Jasińska, J. Wawryszczuk, R. Zaleski, Acta Phys. Pol. A 107, 821 (2005)

Identifiers

DOI

10.12693/APhysPolA.113.1543