超音波噴射による熱分解による磁気および多孔なナノスフィア
Won Hyuk Suh1, Kenneth S Suslick
1School of Chemical Sciences, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Journal of the American Chemical Society
|August 25, 2005
まとめ
研究者らは家用加湿器から超音波噴射熱分解を用いて,多孔性のシリカナノ粒子を作り出した. この方法により,孔のサイズが制御され,コバルトナノ粒子が効率的に封じ込められ,酸化に抵抗するナノスフィアが生成されます.
科学分野:
- 材料科学 材料科学とは
- ナノテクノロジー ナノテクノロジー
- 化学工学は化学工学というものです.
背景:
- ナノ材料を合成するための費用対効果の高い方法の開発は,高度なアプリケーションにとって極めて重要です.
- 超音波スプレー・パイロリシスは,ナノ粒子製造のための汎用的なプラットフォームを提供します.
- シリカナノ粒子の多孔性と表面特性を制御することは,それらの機能化の鍵です.
研究 の 目的:
- 毛細なシリカナノ粒子を生産するための安価な超音波スプレー・パイロリシス方法を開発する.
- シリカ有機複合物の in situ 形成とその後の熱分解を調査する.
- フェロ磁性コバルトナノ粒子が,多孔性のシリカの中に封じ込められていることを示すために.
主な方法:
- 家庭用加湿器から安価な高周波超音波発電機を,超音波噴霧熱分解のために使った.
- in situポリメリゼーションおよびその後のポリマー熱分解のための2つの加熱ゾーンシステムを採用しました.
- 粒子の形態学と表面積を制御するために,シリカと有機単体比を変化させた.
- SEM,TEM,EDS,XPS,SQUIDを用いて,シリカとコバルトで封じ込められた多孔性のナノスフィアの特徴を明らかにした.
主要な成果:
- ナノメートルスケールの多孔性を有する亜マイクロメートルのシリカ粒子を成功裏に生成しました.
- シリカと有機モノメアの比率を調整することによって,シリカ粒子の形態学と表面積の制御が実証されています.
- シリカマトリックス内のフェロ磁性コバルトナノ粒子の効率的な封じ込みを,単一フロープロセスで達成しました.
- その結果生じたコバルト-シリカナノスフィアは,空気酸化に対する高い耐性を示した.
結論:
- 調節可能な多孔性シリカナノ粒子を生成するために,経済的かつ効果的な超音波スプレー・パイロリシス技術が確立されました.
- 開発された方法は,磁性ナノ粒子を保護性シリカマトリックスに容易に組み込むことを可能にします.
- 生成された酸化抵抗性コバルト-シリカナノスフィアは,触媒,センサー,磁気貯蔵における様々な応用の可能性を秘めています.
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