排斥する表面. 排斥する表面. 表面を超反射剤に変えて,完全に濡らした液体でさえ完全に濡らします
Tingyi Leo Liu1, Chang-Jin C J Kim2
1Department of Mechanical and Aerospace Engineering, University of California, Los Angeles (UCLA), Los Angeles, CA 90095, USA.
Science (New York, N.Y.)
|November 29, 2014
まとめ
研究者らは,あらゆる物質を,低エネルギー流体への挑戦を含むすべての液体に対して超反射性にする新しい二重反射性表面構造を開発しました. この画期的な進歩は,防水性コーティングの必要性をなくし,耐久性を向上させました.
科学分野:
- マテリアルサイエンス 材料科学
- 表面化学について
- ナノテクノロジー ナノテクノロジー
背景:
- 従来のスーパーヒドロホビックおよびスーパーオレホビック表面は,水害を嫌う材料の粗化に依存しています.
- 既存の表面は,フッ素溶媒のような非常に低エネルギー液体を排斥できず,非常に水嫌性の高い材料さえも容易に濡らします.
研究 の 目的:
- 材料の排水性から独立して超反発性の表面を作るための普遍的な方法を示す.
- 最も挑戦的な低エネルギー液体さえも撃退できる表面を設計する.
主な方法:
- 特定のダブルリエントラント幾何学を持つマイクロおよびナノ構造の表面の製造.
- 超反射性を達成するために,水害性コーティングなしで,粗さのみを使用します.
- シリカ,金属,およびポリマー基板上で,パーフルオロヘキサンを含む幅広い液体の表面性能をテストします.
主要な成果:
- シリカ,金属,およびポリマーの表面で超オムニフォビシティを達成し,二重リエントラント構造のみを使用します.
- パルフルオロヘキサンを含む,テストされたすべての液体を排斥する能力を実証しました. 排斥が非常に難しい流体です.
- スーパーオムニフォビックシリカ表面は,例外的な熱安定性 (>1000°C) とバイオフォリングに対する耐性を示した.
結論:
- ダブルリエントラント構造は,液体と固体の接触を最小限に抑えることで,あらゆる材料に対する超反射性を可能にします.
- このアプローチは,低エネルギー液体を退避するための従来の方法の限界を克服します.
- 開発された表面は,高温および抗バイオフォーリング特性を備えたスーパーオムニフォビシティのための汎用的で堅牢でコーティングのないソリューションを提供します.
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