Au-Pd コア・シェルナノ粒子のイン・シトゥー運動および熱力学的成長制御

Shu Fen Tan^1,2, Geeta Bisht^1,2, Utkarsh Anand^1,2

¹Department of Physics , National University of Singapore , Singapore 117551.

Journal of the American Chemical Society

|August 14, 2018

まとめ

研究者は,現地伝送電子顕微鏡を用いて,金パラジウムコアシェルのナノ粒子形成を調査した. パラジウム殻の成長メカニズムに影響を与えることでナノ粒子の形状を制御し,設計の柔軟性を高めます.

科学分野:

材料科学
ナノテクノロジー
物理化学

背景:

ワンポット・ウェット・ケミカル・シンセシスは,形状と組成を制御したナノ粒子 (NP) の直接的な経路を提供します.
NP形成のメカニズムを理解することは,正確な合成に不可欠ですが,実験的に困難です.

研究の目的:

異なる反応条件下で金 (Au) コア-パラジウム (Pd) シェルNPの形成メカニズムを調査する.
NPの形状と殻の成長の制御における反応温度の役割を解明する.

主な方法:

液体細胞伝達電子顕微鏡 (TEM) を利用して,NP形成を動的に観察した.
動力学および熱力学的に制御された合成レジームを研究するために,反応温度を変化させた.

主要な成果:

Au-Pd NPの温度に依存する形状調整が実証され,ナノ棒を矢目または立方形のコアシェル構造に変換します.
反応温度によってパラジウム殻の成長が動力学的に支配的な経路と熱力学的に支配的な経路に切り替わることが観察されました
異なる運動条件下でのシェル形成を決定する.

結論:

温度によるNP形成のメカニズム的な洞察は,形状と組成の制御を強化します.
この研究は,様々な技術的な応用のための量身製のナノ粒子を合成するための基盤を提供します.

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