تقرير
Negative-charge-storing mechanism of potassium-ion electrets used for vibration-powered generators: Microscopic study of a-SiO2 with and without potassium atoms
| العنوان: | Negative-charge-storing mechanism of potassium-ion electrets used for vibration-powered generators: Microscopic study of a-SiO2 with and without potassium atoms |
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| المؤلفون: | Nakanishi, Toru, Miyajima, Takeshi, Chokawa, Kenta, Araidai, Masaaki, Toshiyoshi, Hiroshi, Sugiyama, Tatsuhiko, Hashiguchi, Gen, Shiraishi, Kenji |
| المصدر: | Appl. Phys. Lett. 117, 193902 (2020) |
| سنة النشر: | 2020 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Materials Science, Condensed Matter - Other Condensed Matter |
| الوصف: | A potassium-ion electret, which is a key element of vibration-powered microelectromechanical generators, can store negative charge almost permanently. However, the mechanism by which this negative charge is stored is still unclear. We theoretically study the atomic and electronic structures of amorphous silica (a-SiO2) with and without potassium atoms using first-principles molecular-dynamics calculations. Our calculations show that a fivefold-coordinated Si atom with five Si-O bonds (an SiO5 structure) is the characteristic local structure of a-SiO2 with potassium atomsm, which becomes negatively charged and remains so even after removal of the potassium atoms. These results indicate that this SiO5 structure is the physical origin of the robust negative charge observed in potassium-ion electrets. We also find that the SiO5 structure has a Raman peak at 1000cm-1. Comment: 5 pages, 4 figures |
| نوع الوثيقة: | Working Paper |
| DOI: | 10.1063/5.0029012 |
| URL الوصول: | http://arxiv.org/abs/2009.04116 |
| رقم الأكسشن: | edsarx.2009.04116 |
| قاعدة البيانات: | arXiv |
| DOI: | 10.1063/5.0029012 |
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