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 similar to 0.36-0.38 ns, corresponding to di-/tri-atomic vacancies in g-As-Se matrix.