Low Temperature Physics: 42, 601 (2016); https://doi.org/10.1063/1.4959021
Физика Низких Температур: Том 42, Выпуск 7 (Июль 2016), c. 764-769    ( к оглавлению , назад )

Positron annihilation characterization of free volume in micro- and macro-modified Cu0.4Co0.4Ni0.4Mn1.8O4 ceramics

H. Klym1, A. Ingram2, O. Shpotyuk3,4, I. Hadzaman5, V. Solntsev6, O. Hotra7, and A.I. Popov8

1Lviv Polytechnic National University, Ukraine
E-mail: klymha@yahoo.com; halyna.i.klym@lpnu.ua

2Physics Faculty of Opole University of Technology, Poland
3Vlokh Institute of Physical Optics, Lviv, Ukraine

4Institute of Physics of Jan Dlugosz University, Poland
5Drohobych Ivan Franko State Pedagogical University, Ukraine

6V.E. Lashkaryov Institute of Semiconductor Physics of the National Academy of Sciences of Ukraine, Kiev, Ukraine

7Lublin University of Technology, Poland
8Institute of Solid State Physics, University of Latvia, Latvia

Received May 4, 2016


Free volume and pore size distribution size in functional micro and macro-micro-modified Cu0.4Co0.4Ni0.4Mn1.8O4 ceramics are characterized by positron annihilation lifetime spectroscopy in comparison with Hg-porosimetry and scanning electron microscopy technique. Positron annihilation results are interpreted in terms of model implication positron trapping and ortho-positronium decaying. It is shown that free volume of positron traps are the same type for macro and micro modified Cu0.4Co0.4Ni0.4Mn1.8O4 ceramics. Classic Tao-Eldrup model in spherical approximation is used to calculation of the size of nanopores smaller than 2 nm using the ortho-positronium lifetime.

PACS: 78.70.Bj Positron annihilation;
PACS: 71.60.+z Positron states;
PACS: 81.05.Mh Cermets, ceramic and refractory composites;
PACS: 82.30.Gg Positronium chemistry.

Key words: ceramics, free volume, nanopores, positron trapping, positronium decaying.

Published online: May 25, 2016