Glass - Back to the Future!



Presenting Author:
Shiro Kubuki
<Kubuki@tmu.ac.jp>

article posted 7 April 2016


Shiro KubukiGraduated at Kyshu University (Fukuoka, Japan) in 1997 studying material science, focusing on a relationship between local structure and infrared light transmittance of aluminate and gallate glasses. After obtaining a PhD degree in science, he has investigated several functional glasses such as conductive vanadate, photocatalytic silicate by applying 57Fe- and 119Sn-Mössbauer spectroscopies. Please check the list of papers and conference presentations.






Mössbauer study of photocatalytic iron alumino-sililcate glass and its possibilities of preparation from waste slag

Shiro Kubuki, Kosuke Sunakawa, Balazs Kobzi, Yusuke Iida, Erno Kuzmann*, Zoltán Homonnay* & Tetsuaki Nishida**
Graduate School of Science and Engineering, Tokyo Metropolitan University. Minami-Osawa 1-1, Hachi-Oji, 192-0397, JAPAN


The relationship between visible light photocatalytic ability and structure of iron-containing silicate glass with the composition of 15Na2O.15CaO.(70-x).SiO2.xFe2O3 glass (abbreviated as xNCFS, 0<x<50 mass%) was investigated by 57Fe-Mössbauer spectroscopy and methylene blue degradation test. 57Fe-Mössbauer spectrum of xNCFS glass with ‘x’ of 50 heat treated at 1000°C for 100 min composed of a paramagnetic doublet with the isomer shift (delta) of 0·24 mm s-1 and quadrupole splitting (Delta) of 0·99 mm s-1 due to distorted FeIIIO4 tetrahedra, and a magnetic sextet with a delta of 0·36 mm s-1 and internal magnetic field (Hint) of 51·8 T due to hematite [1]. A remarkable decrease in MB from 10 µm to 0·0 µmol with the rate constant (k) of 2·87×10-2 h-1 was observed for the degradation test using heat-treated 50NCFS glass under visible light irradiation [1]. On the other hand, the larger k value of 9·26×10-2min-1 was estimated for heat-treated iron alumino-silicate glass with the composition of 15Na2O.15CaO.40Fe2O3.(30-y)SiO2.yAl2O3 (abbreviated as yNCFAS, 0<y<20 mass%) [2], indicating that the iron silicate enhances the photocatalytic activity by introduction of Al2O3. As a result of elemental analysis, waste slag exhausted from a household garbage combustion plant of Tokyo consisted of SiO2 (23·3%), CaO (21·8%), Al2O3 (16·7%), Fe2O3 (11·4%), Na2O (6·57%), etc. These results imply that the discarded waste slag can be recycled as a visible light activated photocatalyst by slightly modifying the chemical components.
Figure 1. MB degradation test using heat-treated 11NSFAS

References
[1] S. Kubuki, J. Iwanuma, Y. Takahashi, K. Akiyama, Z. Homonnay, K. Sinkó, E. Kuzmann, T. Nishida, J. Radioanal. Nucl. Chem., 301(1), 1-7 (2014).
[2] Y. Iida, K. Akiyama, B. Kobzi, K. Sinkó, Z. Homonnay, E. Kuzmann, M. Ristic´, S. Krehula, T.Nishida, S. Kubuki, J. Alloys Comp., 645, 1-6 (2015).

Acknowledgment:
This work is financially supported by International Research Collaboration Funds of TMU, Grant-in Aid in Japan No. 26630321 and Magyar-Japán TéT program (TÉT_12_JP-1-2014-0025).

* Faculty of Science, Eötvös Loránd University. Pázmány P. s. 1/A, 1117 Budapest, HUNGARY
** Faculty of Humanity-Oriented Science and Engineering, Kinki University. Kayanomori 11-6, Iizuka, Tokyo 820-8555, JAPAN