Thermoanalytical multi-research on nanomilling-driven reamorphization in glassy arsenoselenides

Nanostructurization responses from nanomilling-driven polyamorphic transitions are examined in glassy arsenoselenides AsxSe100−x (0 < x < 70) employing the DSC-TOPEM complemented with X-ray powder diffraction and Raman microscopy study. Calorimetric heat transfer phenomena in these alloys undergoing reamorphization are found to be compositionally dependent. The nanomilling-driven size-induced glass transition temperature Tg depression prevails in the Se-rich network alloys (10 < x < 40) built of Se chains branching AsSe3 pyramids. Medium-range structural changes occur in network organization of these alloys, when position of the first sharp diffraction peak (FSDP) in the XRPD patterning remains invariant, and the FSDP width is increased. In AsxSe100−x alloys possessing cis-/trans-configurated Se chains (0 < x < ~ 10), this effect is balanced by quasi-molecular-to-network (ring-to-chain) transition resulting in slight configuration-enhanced Tg decrease. Domination of thioarsenide-type As4Sen molecules (n = 4,3,0) in molecular-network-structured alloys (40 < x < 70) results in nanomilling-driven network-enhanced Tg increase, and this strong effect being emerged from interplay between disrupted intermediate- and enhanced extended-range order. The nanomilled As-rich alloys becomes notably stressed due to destruction of thioarsenide-type molecules followed by incorporation of their derivatives into a newly polymerized glassy network. Molecular-to-network nature of this reamorphization transition is proved by weakening and broadening of the respective Raman-active vibrational modes in these alloys.