| Texto completo | |
| Autor(es): |
Lancelotti, Ricardo F.
;
Chuang, Shih-Yi
;
Zanotto, Edgar D.
;
Sen, Sabyasachi
Número total de Autores: 4
|
| Tipo de documento: | Artigo Científico |
| Fonte: | ACTA MATERIALIA; v. 285, p. 9-pg., 2024-12-19. |
| Resumo | |
This study investigates the effect of alpha-relaxation induced by physical aging due to a down-jump in fictive temperature (Tf) on the alkali ion hopping dynamics and the resulting ionic conductivity in different network oxide glass-forming systems. Electrochemical impedance spectroscopy, differential scanning calorimetry, and density measurements were used to analyze this effect. Results from ex situ and in situ aging experiments show excellent agreement and demonstrate that alpha-relaxation during aging significantly reduces the ionic conductivity of the glass as its density increases and Tf decreases. In single-alkali Li disilicate and Li metaphosphate glasses, the migration enthalpy Delta Hm of ionic conduction remains constant after aging, while the migration entropy Delta Sm decreases, leading to a corresponding reduction in the hopping rate of mobile alkali ions. In contrast, in the mixed-modifier Na-Mg metaphosphate glass, both Delta Hm and Delta Sm increase after aging. This behavior is potentially explained by a spatial redistribution of Na and Mg cations likely occurring alongside alpha-relaxation during aging. The findings suggest that significant increases in the ionic conductivity of a glass, even by orders of magnitude, can be achieved by raising its Tf. This implies that fast-quenched glass products, such as thin films or fibers, may have novel applications as sensors and solid electrolytes. (AU) | |
| Processo FAPESP: | 22/07679-8 - Origem em escala atômica da relaxação estrutural de vidros metassilicato de chumbo e dissilicato de lítio |
| Beneficiário: | Ricardo Felipe Lancelotti |
| Modalidade de apoio: | Bolsas no Exterior - Estágio de Pesquisa - Doutorado |
| Processo FAPESP: | 13/07793-6 - CEPIV - Centro de Ensino, Pesquisa e Inovação em Vidros |
| Beneficiário: | Edgar Dutra Zanotto |
| Modalidade de apoio: | Auxílio à Pesquisa - Centros de Pesquisa, Inovação e Difusão - CEPIDs |
| Processo FAPESP: | 21/03374-5 - Relaxação estrutural de vidros e sua influência em outros processos dinâmicos |
| Beneficiário: | Ricardo Felipe Lancelotti |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |