BaSnO3における強力な近赤外線発光
Hiroshi Mizoguchi1, Patrick M Woodward, Cheol-Hee Park
1Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210-1185, USA.
Journal of the American Chemical Society
|August 5, 2004
まとめ
バリウム亜鉛酸化物 (BaSnO3) は,欠陥状態のため,室温で強い近赤外線 (NIR) 発光を示す. このユニークな性質は,Sn2+) ドナーレベルを含む電子穴再結合に起因する可能性がある.
科学分野:
- マテリアルサイエンス 材料科学
- 固体物理 固体物理学
- 発光する光度 (luminescence)
背景:
- バリウムスタナート (BaSnO3) はペロブスキート材料で,光電子機器の潜在的応用がある.
- その光発光特性を理解することは,材料設計とデバイス開発において極めて重要です.
研究 の 目的:
- 室温および低温下でのBaSnO3の近赤外線 (NIR) および可視光発光を調査する.
- ストロンチウム置換によるBa{1-x) Sr{-x) SnO3.3の光発光特性に対する影響を調査する.
主な方法:
- 粉末X線微分光と光発光 (PL) スペクトロスコピー.
- 室温 (RT) と77Kでの刺激と放射スペクトルの測定.
- 発光寿命とストークスシフトの分析.
主要な成果:
- 905nmを中心とした強力なNIR放射で,RTのBaSnO3で観測された1.9 eVの大きなストークスシフトがRT.で観測されました.
- 発光寿命 (7-18 ms) は,欠陥状態の関与を示唆しています.
- 低温で目に見える放射が現れ,NIR放射の強度が低下するにつれて増加します.
- ストロンチウム置換はバンドギャップとNIR放射をシフトさせ,ストークスシフトを増加させます.
結論:
- BaSnO3の異常なNIR光発光は,Sn2+と関連した占有ドナーレベルと光生成された穴の再結合から生じる可能性が高い.
- 欠陥状態は,観測された光特性において重要な役割を果たします.
- ストロンチウム含有量を調節することで,Ba{1-x) Sr{x) SnO3.3の光電子特性を変えることができます.
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