高エントロピー合金ナノ粒子の炭熱ショック合成
Yonggang Yao1, Zhennan Huang2, Pengfei Xie3
1Department of Materials Science and Engineering, University of Maryland, College Park, MD 20742, USA.
Science (New York, N.Y.)
|March 31, 2018
まとめ
研究者らは,高エントロピー合金ナノ粒子 (HEA-NP) を最大8つの元素で作成するための新しい炭熱ショック方法を開発しました. これらの高度なナノ粒子は,アンモニア酸化触媒の高効率性を示しています.
科学分野:
- 材料科学
- ナノテクノロジー
- カタリシス
背景:
- 単一のナノ粒子に 混合できない複数の元素を組み込むことは 科学的に価値がありますが 合成的に困難です
- 従来の方法は 複雑な合金ナノ粒子を作るのに苦労します
研究 の 目的:
- 複数の要素を持つ単相固体溶液ナノ粒子を合成するための一般的で制御可能な方法を示す.
- これらのナノ粒子の有用性を示すために
主な方法:
- 炭酸熱ショック (CTS) を利用して,炭酸基板に熱ショック先駆体金属塩混合物 (~2000 K,55 msの持続時間,~10^5 K/sの加熱速度) を使用します.
- CTSパラメータ (基板,温度,持続時間,加熱/冷却速度) を制御し,ナノ粒子化学,サイズ,相を調整する.
- 高エントロピー合金ナノ粒子 (HEA-NP) の合成
主要な成果:
- 単相固体溶液HEA-NPに 8つの異なる元素を成功裏に合金した.
- ナノ粒子組成,サイズ,相 (固体溶液対相分離) の制御が実証されている.
- 合成されたHEA-NPを用いたアンモニア酸化触媒で~100%の変換と>99%の窒素酸化選択性を達成した.
結論:
- 炭熱ショック法では,複雑な多成分ナノ粒子を製造するための多用途な経路が提供されます.
- CTSで合成されたHEA-NPは,アンモニアの酸化などの高度な触媒用途に重要な希望を示しています.
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