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JST Press Release

August 23, 2016
Japan Science and Technology Agency (JST)
5-3, Yonbancho, Chiyoda-ku, Tokyo 102-8666

Finding new controlling method for properties of glass:
Tiny amount of electron anions reduces the glass transition temperature more than 100 degrees

Electride is a compound in which electrons serve as anions. A group of Tokyo Institute of Technology and Pacific Northwest National Laboratory led by Professor Hideo Hosono found that electride glass exhibits a property which has not been seen in conventional glasses and succeeded the mechanism.

The glass transition temperature (Tg) of glass is generally determined by the ratio of network forming component to the network breaking component. i.e., the chemical composition of a bulk glass. They successfully prepared the glass of 12CaO・7Al2O3 electride and found that the Tg is distinctly reduced with increasing the concentration of electron anions. When only 3% of oxygen ion is replaced by electrons, the Tg was reduced by more than 100 degrees, which is almost 2 times as large as the magnitude of Tg change when the CaO content is varied from 56 % to 70% (the whole glass formation range). Ab initio molecular dynamics simulation reproduced this result and elucidated that electron anions are so mobile than the constituent ions that local temperature around them is rather higher than the bulk.

Several novel properties are expected for electride glasses which is a novel class of amorphous materials along with applications.

Program Information

R&D Project “Materials Science and Application of Electrides”

Journal Information

Lewis E. Johnson, Peter Sushko, Yudai Tomota, and Hideo Hosono. “Electron anions and the glass transition temperature”. Proceedings of the National Academy of Sciences of the United States of America, doi: 10.1073/pnas.1606891113.


[About Research]
Hideo Hosono, Ph.D.
Director, Materials Research Center of Element Strategy, Tokyo Institute of Technology, Professor, Institute of Innovative Research, Tokyo Institute of Technology
URL: http://www.titech.ac.jp/english/research/stories/hideo_hosono_2.html
URL: http://www.titech.ac.jp/english/research/stories/hideo_hosono_1.html

[About Program]
Daichi Terashita
ACCEL Group, Department of Innovation Research, JST


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