Structure and properties of titanium–zinc borophosphate glasses

✍ Scribed by Ladislav Koudelka; Petr Mos˘ner; Jaroslav Pospís˘il; Lionel Montagne; Gerard Palavit

• Publisher: Elsevier Science
• Year: 2005
• Tongue: English
• Weight: 307 KB
• Volume: 178
• Category: Article
• ISSN: 0022-4596
• DOI: 10.1016/j.jssc.2005.03.025

✦ Synopsis

The structure of 50ZnO-10B 2 O 3 -40P 2 O 5 +xTiO 2 glasses prepared by slow cooling (for x ¼ 0-24 mol% TiO 2 ) or by quenching (for x ¼ 28-64 mol% TiO 2 ) was studied by Raman, 31 P and 11 B MAS NMR spectroscopy. TiO 2 incorporates into the glass structure, which results in a decrease in the molar volume and an increase in the glass transition temperature. According to Raman spectra Ti atoms form distorted TiO 6 octahedra and their incorporation into the structural network results in the depolymerization of phosphate chains. 11 B NMR spectra of the glasses with increasing TiO 2 content show gradual changes from one symmetrical signal of B(OP) 4 units to a broad complex signal which was separated into five signals ascribed to four different types of BO 4 units and one BO 3 unit. With increasing TiO 2 content a part of boron atoms changes from tetrahedral BO 4 to trigonal BO 3 units, which is ascribed to the formation of TiO 6 units in the glass structure.