Autor(es)

Dias, Jeferson A. ; Santagneli, Silvia H. ; Rodrigues, Ana C. M. ; Boas, Naiza V. ; Messaddeq, Younes

• Tipo de documento: Artigo Científico
• Fonte: Journal of Physical Chemistry C; v. 127, n. 13, p. 19-pg., 2023-04-06.

Resumo

In this paper, the effects of crystallization advance on the material structure and electrical properties of lithium-ion Na+ super ionic conductor (NASICON) glass ceramics were investigated. Glasses with Li1.5Al0.5Ge1.5(PO4)(3) and Li1.5Sc0.17Al0.33Ge1.5(PO4)(3) compositions were crystallized in controlled conditions to obtain gradual increment of the volume crystallized fraction. The glass-to-crystal transformation was then monitored by differential scanning calorimetry analysis (DSC), X -ray diffractometry (XRD), Raman spectroscopy, solid-state nuclear magnetic resonance spectroscopy (MAS NMR), and electron microscopy, along with chemical analyses. Finally, the electrical properties of the specimens were evaluated by impedance spectroscopy to observe the changes in electrical properties according to the crystallization advance. Results revealed that glasses containing scandium are more stable against crystallization than their neat counterparts. Crystallization led to the formation of single-phase NASICON glass ceramics. Scandium induced a lattice expansion of the NASICON structure. Furthermore, crystallization induces remarkable structural changes in the materials as a whole, either in local order or in medium to long order. No important increase in conductivity was observed in earlier stages of crystallization. After the percolation of crystals, conductivity increases sharply and the remaining glassy phase has little impact on the total conductivity of the material. Scandium expands the rhombohedral structure but increases the glass stability and reduces the sizes of crystals for the fully crystallized glass ceramics. Glass ceramics with larger grains are more propitious for conductivity than the more refined ones. Therefore, this paper offers key information about the understanding of NASICON crystallization and its structural evolution, providing important insights into the crystallization of these electrolytes. (AU)

• Processo FAPESP: 19/25756-7 - Estudo da conversão ascendente em vidros dopados com lantanídeo para aplicação de células solares
• Beneficiário: Jeferson Almeida Dias
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 19/15227-7 - Manufatura aditiva promovendo a saúde humana: desenvolvimento de sensores, biossensores e embalagens ativas/inteligentes para alimentos
• Beneficiário: Sidney José Lima Ribeiro
• Modalidade de apoio: Auxílio à Pesquisa - Regular
• Processo FAPESP: 15/22828-6 - Ultrapassando as fronteiras de fibras ópticas: da fotônica até optogenética e monitoramento de meio ambiente
• Beneficiário: Younes Messaddeq
• Modalidade de apoio: Auxílio à Pesquisa - Programa SPEC
• Processo FAPESP: 18/24735-3 - Correlação entre a estrutura e as propriedades investigada por RMN multinuclear no estado sólido em materiais desordenados
• Beneficiário: Silvia Helena Santagneli
• Modalidade de apoio: Auxílio à Pesquisa - Regular