The Science & Technology
of Glass
Cambridge - Monday 4th to
Wednesday 6th September 2017



Quyen Huyen Le
<lhquyen@ctuet.edu.vn>

article posted 14 June 2017

2006: B.Sc., Chemical Engineering, CanTho University, Viet Nam

2009: Master of Engineering Advanced Manufacturing Technology, University of South Australia, Australia. 2015: Starting PhD at Otto Schott Institute of Materials Research, Friedrich Schiller University of Jena, Germany.


Effect of AlF3 and Na2SO4 on the structure and properties of sodium phosphate glasses
Q.H. Le* a,c, E.I. Kamitsos b, L. Wondraczek a



Changes in the structure of three glass series: [(100-x)NaPO3 -xAlF3 (NAPF) in mol%, 0≤ x≤ 40];[ (80-y)NaPO3-20AlF3-yNa2SO4 (NAPFS1), 0≤ y≤ 30] and [70NaPO3-(30-z)AlF3-zNa2SO4 (NAPFS2), 0≤ z≤ 20] were analysed by IR, Raman and NMR spectroscopy. IR and Raman show that the addition of AlF3 to NaPO3 causes major changes on the metaphosphate (Q2) network [1]. The formation of the Raman band at 765 cm-1 (Fig. 1a) can be associated with pyrophosphate dimers, P2O74-, originating from the depolymerization of metaphosphate chains [2]. Charge balancing of P2O74- by both Na+ and Al3+ ions causes the up-shift of the υs(PO32-) mode at ~ 1040-1090 cm-1, and the creation of Al-O-P bridging bonds [3]. In addition, transition temperatures as well as elastic modulus also increase with raising amount of AlF3. As a part of NaPO3 or AlF3 in NAPF glasses were replaced by Na2SO4 (NAPFS1 and NAPFS2), however, the chains ensemble is retained. Na2SO4 leads to a decrease in transition temperatures, but elastic modulus remain stable.

Reference:

[1] D. Möncke, D. Ehrt, et al. Comparative spectroscopic investigation of different types of fluoride phosphate glasses. Phys. Chem. Glasses: Eur.J. Glass Sci. Technol. B, December 2007, 48 (6), 399-402.
[2] D. Philip, B. L. George and G. Aruldhas. IR and Polarized Raman Spectra of Na4P2O7.10H2O. Jounal of Raman spectroscopy, vol. 21, 523-524 (1990).
[3] B. N. Nelson and G. J. Exarhos. Vibrational spectroscopy of cation-site interactions in phosphate glasses. J.Chem. Phys. 71(7), 1 Oct. 1979.
[4] W. A. Dollase, L. H. Merwin and A. Sebald. Structure of Na3-3xAlxPO4, x = 0 to 0.5. Journal of Solid State Chemistry 83, 140-149 (1989).

Institutions:

aOtto-Schott-Institut, Friedrich- Schiller-Universität, Fraunhoferstraße 6, 07743 Jena, Germany
bNational Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, Vass. Constantinou Ave. 48, 11635 Athens, Greece
cCan Tho University of Technology, 256 Nguyen Van Cu, Can Tho, Vietnam