Nanocomposites and nanomaterials

Positronics in contemporary nanocomposites science and engineering:  the case of multinanoparticulate substances
Ingram Adam1*,  Shpotyuk Oleh2,3, Filipecki Jacek2, Shpotyuk Yaroslav4,5 

1 Opole University of Technology, Ozimska 75., Opole 45370, Poland
E-mail: a.ingram@po.opole.pl
2 Jan Dlugosz University in Czestochowa, al. Armii Krajowej 13/15, Czestochowa  42201, Poland
3 O.G. Vlokh Institute of Physical Optics, Dragomanov 23, Lviv 79005,, Ukraine
4 Institute of Physics, University of Rzeszow, Pigonia 1., Rzeszow, 35959, Poland
5 Ivan Franko National University of Lviv, Tarnavskogo 107, Lviv 79017, Ukraine

Possibilities of positron annihilation lifetime (PAL) spectroscopy applied to characterize nanosization processes under high-energy mechanical milling are analyzed for multiparticulate arsenical-based systems, such as monoparticulate As4S4, biparticulate As4S4/Fe3O4 and triparticulate As4S4/ZnS/Fe3O4. The algorithm to treat registered PAL spectra for such substances within three-state mixed trapping model evolving competitive channels of positron and positroniun Ps (bound electron-positron state) channels (x3-x2-CDA, coupling decomposition algorithm) [1,2] is given. It is shown that coexistence of nanocrystalline As4S4 phase and supplemented amorphous substance is crucial feature of these materials, the latter being generated owing to reamorphization of disordered phase initially existed in arsenic sulphide prepared by conventional synthesis from elemental precursors and direct milling-driven vitrification of nanocrystalline As4S4 phase.

1.	Shpotyuk O., Filipecki J., Ingram A., Golovchak R., Vakiv M., Klym H., Balitska V., Shpotyuk M., Kozdras A. Positronics of subnanometer atomistic imperfections in solids as a high-informative structure characterization tool // Nanoscale Res Lett.-2015.-10.-P. 77-1-5.
2.	Shpotyuk O., Ingram A., Shpotyuk Ya. Free-volume characterization of nanostructurized substances by positron annihilation lifetime spectroscopy // Nucl Instr Meth Phys Res. B.-2018.-416.-P. 102-109.