| Full text | |
| Author(s): |
Almeida Silva, Igor D'Anciaes
;
Rodrigues, Ana Candida M.
;
Eckert, Hellmut
Total Authors: 3
|
| Document type: | Journal article |
| Source: | Journal of the American Ceramic Society; v. 105, n. 12, p. 20-pg., 2022-08-29. |
| Abstract | |
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) | |
| FAPESP's process: | 17/17800-0 - Solid State NMR for the study of structure/property correlations in glassy and glass ceramic materials for energy storage applications |
| Grantee: | Igor d'Anciães Almeida Silva |
| Support Opportunities: | Scholarships in Brazil - Post-Doctoral |
| FAPESP's process: | 13/07793-6 - CeRTEV - Center for Research, Technology and Education in Vitreous Materials |
| Grantee: | Edgar Dutra Zanotto |
| Support Opportunities: | Research Grants - Research, Innovation and Dissemination Centers - RIDC |