%0 Journal Article
%T Nuclear Magnetic Resonance and FTIR Structural Studies on Borosilicate Glasses Containing  Iron Oxide
%A Gomaa El-Damrawi
%A Abdel Meguid Hassan
%A Rawia Ramadan
%A Sammer El-Jadal
%J New Journal of Glass and Ceramics
%P 47-56
%@ 2161-7562
%D 2016
%I Scientific Research Publishing
%R 10.4236/njgc.2016.64006
%X The
structure of borosilicate glasses of composition 30Na<sub>2</sub>O-2Al<sub>2</sub>O<sub>3</sub>-25SiO<sub>2</sub>-xFe<sub>2</sub>O<sub>3</sub><sub></sub>&nbsp;(43-x) B<sub>2</sub>O<sub>3</sub> has been investigated in the composition range of 0.5 20 mol% Fe<sub>2</sub>O<sub>3</sub>. <sup>27</sup>Al, <sup>11</sup>B, <sup>29 </sup>Si MAS NMR and FTIR spectroscopies have been used
to measure the fraction of different structural species in the glasses. It is
evidenced from NMR data <span>that both sodium and
Fe<sub>2</sub>O<sub>3</sub> (in low region up to 7 mol%) are the main glass
modifier.</span> Structural determination for borosilicate glasses with a high
content of (Fe<sub>2</sub>O<sub>3</sub>) was carried out by FTIR spectroscopy,
where both <sup>11</sup>B and <sup>29</sup>Si MAS NMR are impossible because of
the high quantities of paramagnetic iron (III) species present. NMR analysis
was performed on borosilicate glasses containing up to 7 mol% Fe<sub>2</sub>O<sub>3</sub> and the N<sub>4</sub> values obtained by FTIR spectroscopy agree within error
with the <sup>11</sup>B NMR results of the same glass samples. Fe<sub>2</sub>O<sub>3</sub> is a main glass modifier in the low-Fe<sub>2</sub>O<sub>3</sub>-content region
(¡Ü6 mol%). On other hand, it plays the role of glass former at higher content
of Fe<sub>2</sub>O<sub>3</sub>. Increasing both N<sub>4 </sub>of boron
tetrahedral units and chemical shift of silicon nuclei to reach maxima at 5
mol% Fe<sub>2</sub>O<sub>3</sub> confirms the role of Fe<sub>2</sub>O<sub>3</sub> as a glass modifier in the low composition region. On the other hand, fast
decrease in N<sub>4</sub> with further increasing Fe<sub>2</sub>O<sub>3</sub> contents ¡Ý6 mol%) is an evidence for iron oxide to inter the glass network as a
network former.
%K NMR-FTIR-Spectroscopy-Borosilicate-Glasses
%U http://www.scirp.org/journal/PaperInformation.aspx?PaperID=70855