Solid-state NMR investigation of fast sodium ion-conducting glass-ceramics: The system Na3+3x-yRE1-xPySi3-yO9 (RE = Sc, Y)

Autor(es)

Almeida Silva, Igor D'Anciaes ; Rodrigues, Ana Candida M. ; Eckert, Hellmut

• Tipo de documento: Artigo Científico
• Fonte: Journal of the American Ceramic Society; v. 105, n. 12, p. 20-pg., 2022-08-29.

Resumo

Glasses and glass-ceramics of composition Na3+3x-yRE1-xPySi3-yO9 were synthesized using RE = Sc and Y, x = 0.4, and y = 0.0 and 0.3 to obtain multiple-phase glass-ceramics containing the highly conducting Na5RESi4O12 (N5) phase. In addition, the two model compounds Na5ScSi4O12 and Na5InSi4O12 were synthesized. Samples were characterized at two distinct annealing stages using X-ray powder diffraction, electrical conductivity measurements, and multinuclear solid-state magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectroscopy. The N5 phase is dominantly formed for Sc-containing glass-ceramics (both with y = 0.0 and 0.3) at crystallization temperatures above 900 degrees C. For the other glass-ceramics, the crystallized phases were dominantly Na3RESi2O7 (N3), RE = Sc and Y, and Na9YSi6O18 (N9) phases. Si-29 MAS-NMR peak assignments were done with the aid of Si-29{Sc-45} rotational echo adiabatic passage double resonance (REAPDOR) experiments. Si-29 and Na-23 MAS-NMR spectra reveal complex phase compositions and local environment distributions, which could be largely assigned based on known semiempirical chemical shift correlations with average Si-O and Na-O bond distances. P-31 MAS and P-31{Sc-45} REAPDOR NMR results suggest the presence of orthophosphate groups, arguing against the literature model of isostructural substitution of silicon by phosphorus in the N5 phase. (AU)

• Processo FAPESP: 17/17800-0 - Estudo de correlações estrutura/propriedade em vidros e vitrocerâmicas para armazenamento de energia por técnicas de RMN de estado sólido
• Beneficiário: Igor d'Anciães Almeida Silva
• Modalidade de apoio: Bolsas no Brasil - Pós-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