2つの新冠エーテルクラトラートの異常な高温可逆相変遷行動,構造,および介電電鉄特性
Yun-Zhi Tang1, Yin-Mei Yu1, Jian-Bo Xiong1
1School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology , Ganzhou 341000, PR China.
Journal of the American Chemical Society
|September 29, 2015
まとめ
2つの新しいクローンエーテルクラトラートは高温フェロ電気的相変異を示しています. これらの材料は可逆的な構造変化と 顕著な自発的偏りを示し,高度な電子アプリケーションの可能性を秘めています.
科学分野:
- 材料科学
- 固体化学
- クリスタルグラフィー
背景:
- 高温の可逆相変化を持つ分子フェロエレクトリックは希少であり,非常に求められています.
- フェロ電気材料は,センサーやメモリストレージを含む様々な電子機器に不可欠です.
研究 の 目的:
- 高温の鉄電性を持つ新型クローンエーテルクラトラートを合成し,特徴づけること.
- これらの新しい化合物の可逆的な相変遷行動と鉄電特性について調査する.
主な方法:
- 構造分析のための可変温度粉末X線微分法 (PXRD).
- 温度に依存する振動の変化を監視するラーマン光譜法.
- 段階移行中の熱異常を検出するための差分スキャニングカロメトリ (DSC).
- 単一結晶の測定は,自発的偏りなどの鉄電性性を決定します.
主要な成果:
- 2つの新しい冠エーテルクラトラート[Hcha-(18-crown-6) ](+) [BF4](-) (1) と[Hcha-(18-crown-6) ](+) [ClO4](-) (2) が合成された.
- PXRDとラーマン光譜で可逆的な構造的相変化が確認されました.
- DSCと介電異常によって証明された, (1) の約397Kと (2) の約390Kで,フェロ電気的相変遷が発生した.
- (1) の ~3. 27 μC cm−2 と (2) の ~3. 78 μC cm−2 の最適化された自発的偏振値が測定された.
結論:
- 合成されたクローンエーテルクラトラートは高温の有望なフェロ電気特性を示しています.
- これらの材料は可逆的な相変化を示し,熱安定性を要求する用途に適しています.
- 観測された自発的偏振値は,高度な鉄電器で使用する可能性を示しています.
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