Volumetric Nanostructurization in Glassy Arsenoselenides Driven by High‐Energy Mechanical Dry‐ and Wet‐Milling

The method of positron annihilation lifetime (PAL) spectroscopy is employed to study atomic‐deficient free‐volume evolution in nanocomposites prepared by high‐energy mechanical milling of glassy arsenoselenides g‐As‐Se in dry mode and water solution of polyvinylpyrrolidone (PVP). Formalism of x3‐x2‐CDA (coupling decomposition algorithm) describing conversion of bound positron‐electron (positronium, Ps) states into positron traps is applied to identify free‐volume changes in the pelletized PVP‐capped g‐As‐Se nanocomposites in respect to dry‐milled samples. Under wet milling, the inter‐nanoparticle Ps‐decaying sites in preferential PVP environment are shown to replace free‐volume positron traps in dry‐milled g‐As‐Se samples with defect‐specific positron lifetime approaching ∼0.36‐0.38 ns, corresponding to di‐/tri‐atomic vacancies in g‐As‐Se matrix.