圧力誘発相変形,可逆無形化,および有機鉛ブロミドペロブスキートの異常光反応
Yonggang Wang1,2,3, Xujie Lü1, Wenge Yang2,4
1High Pressure Science and Engineering Center, University of Nevada , Las Vegas, Nevada 89154, United States.
Journal of the American Chemical Society
|August 19, 2015
まとめ
水位圧は,有機鉛ブロミドペロブスキート (MAPbBr3) の相変異と可逆性無形化を誘導する. この圧力調節は半導体特性と可視光応答を維持し,光伏装置の可能性を秘めています.
科学分野:
- 材料科学
- 凝縮物質物理学
- 固体化学
背景:
- 液圧圧力は材料の特性を調整する鍵となる技術であり,化学圧力の代替手段である.
- CH3NH3PbBr3 (MAPbBr3) のような有機鉛ブロミドペロブスキットは,新しい用途のための有望な材料です.
- 圧力誘発の相安定性と電子特性を理解することは,材料設計において極めて重要です.
研究 の 目的:
- 34GPaまでの水圧下でのMAPbBr3の相安定性を調査する.
- MAPbBr3の可視光反応を圧力の関数として調べる.
- 圧力を調節したMAPbBr3の潜在的応用を探求する.
主な方法:
- インサイト光発光,電気抵抗,光電流の測定
- 室温で最大34GPaの水圧を適用する.
- 理論分析のための第一原理シミュレーション
主要な成果:
- 2 GPa未満の2つの相変換 (Pm3̅mからIm3̅,それからPnma) と2 GPaから始まる可逆性アモルフィゼーションを観察した.
- 競合する圧縮と無形化効果による異常なバンドギャップの進化 (赤シフトと青シフト).
- 半導体特性と光応答を保持した25GPaの抵抗 (5次元の) の有意な増加.
結論:
- 水位圧は,MAPbBr3の結晶構造と電子特性を効果的に調整することができます.
- MAPbBr3の圧力誘発による無形化は,光の吸収能力を保ちながら,抵抗に大きな変化をもたらします.
- 水圧下でのMAPbBr3は,スイッチやコントローラーとしての光伏装置の応用の可能性を示し,光吸収器としての無形な有機金属複合材料を示しています.
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