BiF3 Incorporation in Na/Ba Mixed Network Modifier Fluoride-Phosphate Glasses: Structural Studies by Solid-State NMR and Raman Spectroscopies

Author(s)

Galleani, Gustavo ^[1] ; Bradtmueller, Henrik ^[2] ; Fares, Hssen ^[3] ; Santagneli, Silvia Helena ^[3] ; Nalin, Marcelo ^[3] ; Eckert, Hellmut ^{[1, 2]}

Affiliation

^[1] Sao Paulo Univ USP, Sao Carlos Inst Phys, BR-13566590 Sao Carlos, SP - Brazil

^[2] Westfalische Wilhelms Univ Munster, Inst Phys Chem, D-48149 Munster - Germany

^[3] Sao Paulo State Univ UNESP, Inst Chem, BR-14800900 Araraquara, SP - Brazil

• Document type: Journal article
• Source: Journal of Physical Chemistry C; v. 124, n. 46, p. 25578-25587, NOV 19 2020.
• Web of Science Citations: 0

Abstract

Bismuth-containing rare-earth codoped fluoride phosphate glasses are promising materials for superbroadband near-infrared (NIR) emission with potential applications in optical amplification. To elucidate their structural organization, this contribution develops a comprehensive multinuclear solid-state single and P-31/F-19 double resonance NMR strategy, applied to glasses in the system (BiF3)(y)(50NaPO(3)-20Ba(PO3)(2)-20NaF-10BaF(2))(100-y) (y = 0, 5, 10, 20, 30, 40). To separately assess the influence of bismuth and fluorine constituents on the network structure, an additional set of ( NaPO3)(50-2x) (Ba(PO3)(2)) (20-x)(NaF)(20+2x)(BaF2)(10+x) (x = 0, 2.5, 5.0, 7.5) glasses was also investigated. Introduction of alkali fluoride ions into phosphate glasses is shown to follow a new network modification scheme involving depolymerization of polyphosphate chains under the formation of F-bonded fluorophosphate units. However, a significant part of the fluoride stays separate, interacting exclusively with metal-ion species. Na-23 MAS and Na-23[P-31] double resonance NMR results are consistent with a local sodium ion environment dominated by phosphate ions in the Bi-free system, whereas in the BiF3-containing glasses, the successive reduction of the dipolar second moment M-2(Na-P) with increasing BiF3 content reflects the expected dilution effect, accompanied by increasing competition of the fluoride ions for ligation with the Na+ ions. (AU)

• FAPESP's process: 18/24735-3 - The correlation between structure and properties as investigated by multinuclear solid state NMR in disordered materials
• Grantee: Silvia Helena Santagneli
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07793-6 - CEPIV - Center for Teaching, Research and Innovation in Glass
• Grantee: Edgar Dutra Zanotto
• Support Opportunities: Research Grants - Research, Innovation and Dissemination Centers - RIDC
• FAPESP's process: 18/03931-9 - Preparation of fluoride-phosphate glass and glass-ceramics doped with rare-earth ions for potential use as radiation detectors
• Grantee: Gustavo Galleani
• Support Opportunities: Scholarships in Brazil - Post-Doctorate
• FAPESP's process: 15/22828-6 - Pushing the boundaries of optical fibers: from photonics to optogenetics and environmental monitoring
• Grantee: Younes Messaddeq
• Support Opportunities: Research Projects - SPEC Program