Tellurite And Fluorotellurite Glasses For Active And Passive

7. Surface properties; MDO 310
binding energy [19]. Intermediates in the glass such as Zn +2 can also result in termination
of the glass network in places, much like Na + , but weakly link it in others [21]. Therefore,
the main O1s peak at around 530.9 eV (82.5 %) eV is a combination of the binding
energies of oxygens within BOs and NBOs in the glass.
The spectrum from the polished surface of glass MOD015 (fig. (7.10)) clearly shows
that the O1s peak attributed to OH at 532.4 eV (46.3 %) has clearly grown, due to
hydrolysis at the exposed glass surface, in addition to the main peak at 530.6 eV (46.5
%). An additional peak can be seen at 533.9 eV (7.2 %), most likely to be due to organic
groups (C-O / C=O) at the glass surface.
7.3.1.3. XPS of fluorotellurite glasses
No XPS studies, to this author’s knowledge, have been performed on fluorotellurite
glasses. However, Chowdari et al. performed XPS studies on CuI containing TeO2
glasses [20].
Fig. (7.11) shows the wide scan XPS spectra of glass MOF001_iii (65TeO2-10Na2O-
25ZnF2 mol. %), which was melted for 1.75 hours with un-fluorinated ZnF2. Na1s, Zn2p,
F1s, Te3d, and O1s peaks were identified and quantification is shown. Quantification
from the wide scan gives a rough estimate of composition, however the high resolution
peaks give more accurate values. The F1s peak (fig. (7.12)) was asymmetric, the higher
energy shoulder at 684.4 eV now almost a separate peak of similar area to the peak at
681.9 eV (51.0 and 49.0 % respectively). This multipeak structure is to be expected, as
although fluorine enters the glass in ZnF2, it will probably bond to other cations in the