Positron Annihilation Studies of Mesoporous Iron-Molybdenum Modified MCM-41 Silica

• Authors: Z. Surowiec , M. Wiertel , W. Gac , M. Budzyński
• Languages of publication: EN

Abstracts

EN

Iron-molybdenum modified MCM-41 mesoporous materials were obtained by the application of direct hydrothermal method. An incorporation of iron and molybdenum ions in the synthesis stage led to structural changes of the MCM-41 support. With an increasing metals content, cylindrical pores of silica are destroyed. X-ray diffraction investigations indicated that both iron and molybdenum ions were first embedded in the silica walls and then formed highly dispersed species in the pores. The porous structure of the studied samples was examined by means of N_2 adsorption/desorption and PALS methods. The longest-lived o-Ps lifetime component remains constant but its intensity monotonically decreases, except for the sample with the highest metals content. These results indicate that an effect of o-Ps formation inhibition occurs.

Keywords

EN

34.80.Lx   78.67.Bf   78.70.Bj   62.23.Pq   78.67.Sc  

• Publisher: Institute of Physics, Polish Academy of Sciences
• Journal: Acta Physica Polonica A
• Year: 2014
• Volume: 125
• Issue: 3
• Pages: 789-792

Dates

published

2014-03

References

• [1] C.T. Kresge, M.E. Leonowicz, W.J. Roth, J.C. Vartuli, J.S. Beck, Nature 359, 710 (1992), doi:10.1038/359710a0
• [2] R.S. Robert, A. Rafael, A.D. James, W.R. Thatcher, Micropor. Mesopor Mater. 66, 53 (2003), doi:10.1016/j.micromeso.2003.08.019
• [3] A. Taguchi, F. Schüth, Micropor. Mesopor. Mater. 77, 1 (2005), doi:10.1016/j.micromeso.2004.06.030
• [4] D. Liu, W.N. Evelyn Cheo, Y.W. Yvonne Lim, A. Borgna, R. Lau, Y. Yang, Catal. Today 154, 229 (2010), doi:10.1016/j.cattod.2010.03.054
• [5] Z. Surowiec, M. Wiertel, M. Budzyński, W. Gac, Nukleonika 58, 87 (2013)
• [6] Z. Surowiec, M. Wiertel, M. Budzyński, J. Sarzyński, J. Goworek, J. Non-Cryst. Solids 354, 4271 (2008), doi:10.1016/j.jnoncrysol.2008.06.032
• [7] I. Alonso-Lemu, Y. Verde-Gómez, L. Álvarez-Contreras, Int. J. Electrochem. Sci. 6, 4176 (2011)
• [8] A.P.V. Soares, M.F. Portela, A. Kiennemann, Catal. Rev. Sci. Eng. 47, 125 (2004), doi:10.1081/CR-200049088
• [9] G. Centi, F. Fazzini, J.L.G. Fierro, M.L. Granados, R. Sanz, D. Serrano, Stud. Surf. Sci. Catal. 118, 577 (1998), doi:10.1016/S0167-2991(98)80224-3
• [10] K.J. Chao, C.N. Wu, H. Chang, L.J. Lee, S. Hu, J. Phys. Chem. B 101, 6341 (1997), doi:10.1021/jp970609v
• [11] Z. Surowiec, M. Wiertel, A. Marynowska, W. Gac, W. Zawadzki, Nukleonika 58, 137 (2013)
• [12] J. Kansy, Nucl. Instrum. Meth. Phys. Res. A 374, 235 (1996), doi:10.1016/0168-9002(96)00075-7
• [13] M. Wiertel, Z. Surowiec, M. Budzyński, W. Gac, Nukleonika 58, 245 (2013)
• [14] S. Chakrabarti, S. Chaudhuri, P.M.G. Nambissan, Phys. Rev. B 71, 64105 (2005), doi:10.1103/PhysRevB.71.064105
• [15] S. Dannefaer, T. Bretagnon, D. Kerr, J. Appl. Phys. 74, 884 (1993), doi:10.1063/1.354882

Identifiers

DOI

10.12693/APhysPolA.125.789