Narzędzia help

Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników
first last
cannonical link button



Tytuł artykułu

Study on the effect of atmospheric gases adsorbed in MnFe2O4/MCM-41 nanocomposite on ortho-positronium annihilation

Autorzy Wiertel, M.  Surowiec, Z.  Budzyński, M.  Gac, W. 
Treść / Zawartość
Warianty tytułu
Konferencja Polish Seminar on Positron Annihilation (42 nd ; 29.06-01.07.2016 ; Lublin, Poland)
Języki publikacji EN
EN In this paper, results of positron annihilation lifetime spectroscopy (PALS) studies of MnFe2O4/MCM- -41 nanocomposites in N2 and O2 atmosphere have been presented. In particular, the influence of manganese ferrite loading and gas filling on pick-off ortho-positronium (o-Ps) annihilation processes in the investigated samples was a point of interest. Disappearance of the longest-lived o-Ps component with τ5 present in the PAL spectrum of initial MCM-41 mesoporous material in the PAL spectra of MnFe2O4-impregnated MCM-41 measured in vacuum is a result of either a strong chemical o-Ps quenching or the Ps inhibition effects. The intensity I4 of the medium-lived component initially increases, reaching a maximum value for the sample with minimum manganese ferrite content, and then decreases monotonically. Analogous dependence for the intensity I3 of the shortest-lived component shows a maximum at higher MnFe2O4 content. Filling of open pores present in the studied nanocomposites by N2 or O2 at ambient pressure causes partial reappearance of the τ4 and τ5 components, except a sample with maximum ferrite content. The lifetimes of these components measured in O2 are shortened in comparison to that observed in N2 because of paramagnetic quenching. Anti-inhibition and anti-quenching effects of atmospheric gases observed in the MnFe2O4/MCM-41 samples are a result of neutralization of some surface active centers acting as inhibitors and weakening of pick-off annihilation mechanism, respectively.
Słowa kluczowe
EN manganese ferrite   MCM-41 silica   nanocomposite   o-Ps quenching   positronium annihilation  
Wydawca Institute of Nuclear Chemistry and Technology
Czasopismo Nukleonika
Rocznik 2015
Tom Vol. 60, No. 4, part 1
Strony 783--787
Opis fizyczny Bibliogr. 21 poz., rys.
autor Wiertel, M.
  • Department of Nuclear Methods, Institute of Physics, M. Curie-Skłodowska University, 1 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland, Tel.: +48 81 537 6220, Fax: +48 537 6191,
autor Surowiec, Z.
  • Department of Nuclear Methods, Institute of Physics, M. Curie-Skłodowska University, 1 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland, Tel.: +48 81 537 6220, Fax: +48 537 6191
autor Budzyński, M.
  • Department of Nuclear Methods, Institute of Physics, M. Curie-Skłodowska University, 1 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland, Tel.: +48 81 537 6220, Fax: +48 537 6191
autor Gac, W.
  • Faculty of Chemistry, M. Curie-Skłodowska University, 3 M. Curie-Skłodowskiej Sq., 20-031 Lublin, Poland
1. Ajayan, P. M. (2003). Bulk metal and ceramics nanocomposites. In P. M. Ajayan, L. S. Schadler, & P. V. Braun (Eds.), Nanocomposite science and technology (pp. 1–76). Weinheim: Wiley-VCH Verlag GmbH & Co. KgaA.
2. Goworek, T. (2014). Positronium as a probe of small free volumes in crystals, polymers and porous media.Ann. UMCS Chemia, 69(1/2), 1–110. DOI: 10.2478/umcschem-2013-0012.
3. Tao, S. J. (1972). Positronium annihilation in molecular substances. J. Chem. Phys., 56, 5499–5510. DOI:10.1063/1.1677067.
4. Eldrup, M., Lightbody, D., & Sherwood, J. N. (1981). The temperature dependence of positron lifetimes in solid pivalic acid. Chem. Phys., 63, 51–58. DOI:10.1016/0301-0104(81)80307-2.
5. Schrader, D. M., & Jean, Y. C. (1988). Introduction. In D. M. Schrader, & Y. C. Jean (Eds.), Positron and positronium chemistry (pp. 1–26). Amsterdam: Elsevier.
6. Kuo-Sung, L., Hongmin, Ch., Somia, A., Jen-Pwu, Y., Wei-Song, H., Kuier-Rarn, L., Juin-Yih, L., Chien--Chieh, H., & Jean, Y. C. (2011). Determination of free-volume properties in polymers without orthopositronium components in positron annihilation lifetime spectroscopy. Macromolecules, 44, 6818–6826. DOI:10.1021/ma201324k.
7. Zaleski, R., Dolecki, W., Kierys, A., & Goworek, J. (2012). n-Heptane adsorption and desorption on porous silica observed by positron annihilation lifetime spectroscopy. Microporous Mesoporous Mater., 154, 142–147. DOI: 10.1016/j.micromeso.2011.08.032.
8. Beck, J. S., Vartuli, J. C., Roth, W. J., Leonowicz, M. E., Kresge, C. T., Schmitt, K. D., Chu, C. T. W., Olson, D. H., Sheppard, E. W., McCullen, S. B., Higgins, J. B., & Schlenker, J. L. (1992). A new family of mesoporous molecular sieves prepared with liquid crystal templates. J. Am. Chem. Soc., 114(27), 10834–10843.DOI: 10.1021/ja00053a020.
9. Goworek, T., Górniak, W., & Wawryszczuk, J. (1992). The sources of distortions and errors in the analysis of positron lifetime spectra. Nucl. Instrum. Methods Phys. Res. Sect. A-Accel. Spectrom. Dect. Assoc. Equip., 321, 560–570. DOI: 10.1016/0168-9002(92)90068-F.
10. Surowiec, Z., Wiertel, M., Zaleski, R., Budzyński,M., & Goworek, J. (2010). Positron annihilation study of iron oxide nanoparticles in mesoporous silica MCM-41 template. Nukleonika, 55(1), 91–96.
11. Kansy, J. (1996). Microcomputer program for analysis of positron annihilation lifetime spectra. Nucl. Instrum. Methods Phys. Res. Sect. A-Accel.Spectrom. Dect. Assoc. Equip., 374, 235–244. DOI:10.1016/0168-9002(96)00075-7.
12. Dannefaer, S., Bretagnon, T., & Kerr, D. (1993).Vacancy-type defects in crystalline and amorphous SiO2. J. Appl. Phys., 74(2), 884–890. DOI: 10.1063/1.354882.
13. Hassan, H. E., Sharshar, T., Hessien, M. M., & Hemeda, O. M. (2013). Effect of γ-rays irradiation on Mn-Ni ferrites: Structure, magnetic properties and positron annihilation studies. Nucl. Instrum. Methods Phys. Res. Sect. B-Beam Interact. Mater. Atoms, 304, 72–79. DOI: 10.1016/j.nimb.2013.03.053.
14. Chakrabarti, S., Chaudhuri, S., & Nambissan, P. M. G. (2005). Positron annihilation lifetime changes across the structural phase transition in nanocrystalline Fe2O3. Phys. Rev. B, 71, 064105. DOI: 10.1103/PhysRevB.71.064105.
15. Bandyopadhyay, S., Roy, A., Das, D., Ghugre, S. S., & Ghose, J. (2003). Investigation of nanocrystalline CoFe2O4 by positron annihilation lifetimespectroscopy. Philos. Mag., 83, 765–773. DOI:10.1080/0141861021000042271.
16. Mitra, S., Mandal, K., Sinha, S., Nambissan, P. M. G., & Kumar, S. (2006). Size and temperature dependent cationic redistribution in NiFe2O4(SiO2) nanocomposites: positron annihilation and Mössbauer studies. J. Phys. D-Appl. Phys., 39, 4228–4235. DOI:10.1088/0022-3727/39/19/016.
17. Chakraverty, S., Mitra, S., Mandal, K., Nambissan, P. M. G., & Chattopadhyay, S. (2005). Positron annihilation studies of some anomalous features of NiFe2O4 nanocrystals grown in SiO2. Phys. Rev. B, 71, 024115. DOI: 10.1103/PhysRevB.71.024115.
18. Wiertel, M., Surowiec, Z., Gac, W., & Budzyński, M.(2014). Positron annihilation in MnFe2O4/MCM-41 nanocomposite. Acta Phys. Pol. A, 125, 793–797.DOI: 10.12693/APhysPolA.125.793.
19. Kobayashi, Y., Ito, K., Oka, T., & Hirata, K. (2007). Positronium chemistry in porous materials. Radiat. Phys. Chem., 76, 224–230. DOI: 10.1016/j.radphyschem.2006.03.042.
20. Wiertel, M., Surowiec, Z., Budzyński, M., & Gac, W. (2013). Positron annihilation studies of mesoporous iron modified MCM-41 silica. Nukleonika, 58, 245–250.
21. Chuang, S. Y., & Tao, S. J. (1971). Study of various properties of silica gel by positron annihilation. J. Chem. Phys., 54, 4902–4907. DOI: 10.1063/1.1674769.
Kolekcja BazTech
Identyfikator YADDA bwmeta1.element.baztech-9eb6f774-ae11-4d60-a9ad-d13003104d5b
DOI 10.1515/nuka-2015-0141