Mathematical description of absorbance spectra and redox in a Fe and Ce doped silicate glass

T T Volotinen and J M ParkerDept. of Engineering Materials, The University of Sheffield, U.K.

e-Poster presented at GLASSAC14 – <http://www.glassac14.sgt.org>

IntroductionGood quality wine deserves to be protected from the sun’s radiation, particularly blue and UV light, by the bottle material during long term storage in shops. This work explores, how the absorbance spectrum of a 15soda-15lime-70silica glass doped with Ce and Fe can be adjusted to provide such protection. The wine should also appear appetising i.e. the glass colour matters.

Results• Fe2+ ions can be oxidised to Fe3+ ions by adding CeO2 to the batch.• The absorbance spectra of Fe2+, Fe3+, Ce3+ and Ce4+ ions are described by summed Gaussian peaks, and calibrated using the literature data1,2,3. The concentration of these ions can be accurately measured from the measured absorbance spectra.

Mathematical description of absorbance spectra and redox in a Fe and Ce doped silicate glass

T T Volotinen and J M ParkerDept. of Engineering Materials, The University of Sheffield, U.K.

e-Poster presented at GLASSAC14 – <http://www.glassac14.sgt.org>

Measured and fitted absorbance spectrum of a Fe-doped glass

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Difference (Absorbance - Fitted)Fitted sum spectrumGlass 81, NCS/G, doped with 0,50 mol % Fe2O3Spectrum of 0,160 mol % Fe2+Spectrum of 0,855 mol % Fe3+IR-edgeSum of OH-peaks

Mathematical description of absorbance spectra and redox in a Fe and Ce doped silicate glass

T T Volotinen and J M ParkerDept. of Engineering Materials, The University of Sheffield, U.K.

e-Poster presented at GLASSAC14 – <http://www.glassac14.sgt.org>

Measured and fitted absorbance spectrum of a Ce-doped glass

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Glass 230, NCS/G, 0.99 mol % CeO2

Spectrum of 0.90 mol % Ce3+

Spectrum of 0.085 mol % Ce4+

Spectrum of 0.005 mol % Fe2+ cont.

Spectrum of 0.031 mol % Fe3+ cont.

Mathematical description of absorbance spectra and redox in a Fe and Ce doped silicate glass

T T Volotinen and J M ParkerDept. of Engineering Materials, The University of Sheffield, U.K.

e-Poster presented at GLASSAC14 – <http://www.glassac14.sgt.org>

Measured and fitted absorbance spectra of the Ce and Fe doped glasses

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231, Fitted spectrum231, NCS/G, 0.10 mol % Fe2O3 + 0.99 mol % CeO2230, NCS/G, 0.99 mol % CeO2Fitted spectrum208, NCS/G, 0.49 mol % Fe2O3 + 0.99 mol % CeO2 Fitted spectrumGlass 81, NCS/G, doped w ith 0,50 mol % Fe2O3Fitted sum spectrum

Mathematical description of absorbance spectra and redox in a Fe and Ce doped silicate glass

T T Volotinen and J M ParkerDept. of Engineering Materials, The University of Sheffield, U.K.

e-Poster presented at GLASSAC14 – <http://www.glassac14.sgt.org>

Conclusions

• Ion concentrations: [Ce3+], [Ce4+], [Fe2+] and [Fe3+] and redox ratios can be defined from the measured absorbance spectrum with the fitting method.

• A UV- and short visible wavelength absorbing glass can be obtained by using Fe and Ce as dopants.

• The colour of the glass can be chosen between a green and yellow hue by choosing a suitable proportion between Ce and Fe dopant concentrations.

• The absorbance spectrum and glass colour can be designed by computer for a known host glass.

Literature1. Volotinen, Tarja T, 2007, PhD Thesis, Sheffield University. 2. Paul, A and Douglas, R W, 1965, Phys. and Chem. of Glasses, Vol.

6, No. 6, p. 212 – 215.3. Paje S E et al, 2001, Optical Materials, Vol. 17, p. 459 – 469.