Slow-photon effects in inverse-opal TiO2 photocatalysis: evaluation by electron spin resonance spectroscopy
Project/Area Number |
17K06018
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Research Category |
Grant-in-Aid for Scientific Research (C)
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Allocation Type | Multi-year Fund |
Section | 一般 |
Research Field |
Inorganic industrial materials
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Research Institution | Hiroshima University |
Principal Investigator |
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Project Period (FY) |
2017-04-01 – 2020-03-31
|
Project Status |
Completed (Fiscal Year 2019)
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Budget Amount *help |
¥4,940,000 (Direct Cost: ¥3,800,000、Indirect Cost: ¥1,140,000)
Fiscal Year 2019: ¥1,170,000 (Direct Cost: ¥900,000、Indirect Cost: ¥270,000)
Fiscal Year 2018: ¥1,300,000 (Direct Cost: ¥1,000,000、Indirect Cost: ¥300,000)
Fiscal Year 2017: ¥2,470,000 (Direct Cost: ¥1,900,000、Indirect Cost: ¥570,000)
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Keywords | フォトニック結晶 / 低速フォトン / 逆オパール構造 / 二酸化チタン / 電子スピン共鳴法 / 光触媒 / 金属酸化物半導体 / 低速フォトン効果 / 光誘起電荷分離 |
Outline of Final Research Achievements |
TiO2 photonic crystals having an inverse opal (IO) structure were prepared with a high shape accuracy, and the effects of the slow photon (SP) on the yields of photo-generated electrons (trapped electrons like O2- and Ti3+) were investigated.The trapped electrons were quantitatively evaluated at 77 K by electron spin resonance (ESR) spectroscopy for photo-irradiated IO-TiO2 with a small amount of O2 or MeOH. The yields increased by twice when IO-TiO2 was prepared so that the slow photon can contribute to the bandgap excitation of TiO2, as compared with other IO-TiO2 samples where the energy of SP is smaller than the band gap of TiO2. In applying the photonic structure on photochemical reactions, it is important not only to prepare the three dimensional photonic crystal with a higher space accuracy, but also to select a proper solvent used in the reaction, which seriously affects the photophysical property of the photonic crystal.
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Academic Significance and Societal Importance of the Research Achievements |
現在、フォトニック結晶の光物性を光学素子などに応用する研究は急増しているが、光化学反応への応用研究は少ない。本研究成果は、二酸化チタンをフォトニック結晶の構造に作り変えることで、貴金属などを加えることなしで、二酸化チタンの光エネルギーの化学エネルギへの変換効率をさらに向上させることができる可能性を示した。ただし、光化学反応への応用では、フォトニック結晶を高品質かつ高精度に作成する技術の確立だけでなく、媒体(溶媒)の適切な選択も極めて重要である。
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Report
(4 results)
Research Products
(6 results)