電気フィールドの梯度によって誘発される単純な流体における脱混合

Yoav Tsori¹, François Tournilhac, Ludwik Leibler

¹Laboratoire Matière Molle & Chimie (UMR 167 CNRS-ESPCI), Ecole Supérieure de Physique et Chimie Industrielles, 10 rue Vauquelin, 75231 Paris CEDEX 05, France.

Nature

|July 30, 2004

まとめ

非均一な電場は,現在,実用的な条件下で液体混合物の相分離を制御することができます. このブレークスルーにより,オイルの可逆的な脱混合が可能になり,ナノテクノロジーの応用への扉が開きます.

科学分野:

物理化学物理化学について
マテリアルサイエンス材料科学
ナノテクノロジーナノテクノロジー

背景:

液体混合物における相分離は,通常,温度と圧力によって制御されます.
電気場のような外部フィールドは相分離に影響を与えるが,通常は濃度変動による弱い結合により極端な条件を必要とします.

研究の目的:

非均一な電場が,実用的な条件下で液体混合物の相分離を制御できることを予測し,実証する.
フィールド強度と電極の幾何学が脱混合プロセスに及ぼす影響を調査する.

主な方法:

不均等に配置された電極に100Vの電圧を適用する (約. 50マイクロメートル離れています).
パラフィンとシリコンオイル混合物の相分離行動の研究.
電気フィールドの梯度を取り除いた後の脱混合の可逆性を観察する.

主要な成果:

不均一な電場により,パラフィンとシリコン油の混合物が相変化温度より1K上での可逆的な脱混合を成功させた.
効果はフィールド強度に依存し,電極の幾何学が長さスケールを決定した.
フィールド・グラデーションが除去されると,混合物は再び均質になった.

結論:

不均一な電場は,液体混合物における相分離を制御するための実用的な方法を提供します.
この現象は,ナノテクノロジーにおいて,特に小さな導電性物体の近くにおいて,潜在的な応用がある.

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