原子レベルでのPd-Pt合金化と,二金属ナノ粒子における水素貯蔵能力の大幅な強化は,水素吸収/分解のプロセスによってコア/シェル構造から再構築された
Hirokazu Kobayashi1, Miho Yamauchi, Hiroshi Kitagawa
1Department of Chemistry, Faculty of Science, Kyushu University, Hakozaki, Fukuoka 812-8581, Japan.
Journal of the American Chemical Society
|April 6, 2010
まとめ
研究者らは,改良された水素貯蔵を備えた新しいパラジウム・プラチナ (Pd-Pt) 固体溶液ナノ粒子を作り出した. この原子レベルの混合は,構成によって調整可能な水素容量を大幅に増加させます.
科学分野:
- 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
- 物理化学 物理化学
背景:
- コアシェルのナノ粒子は,通常,異なる層で合成されます.
- 合金ナノ粒子の均質な原子混合を達成することは,合成の課題を提示します.
- 水素貯蔵材料には,効率的で調節可能な特性が必要です.
研究 の 目的:
- 固体溶液ナノ粒子の均質なパラジウム・プラチナ (Pd-Pt) を生成する方法を開発する.
- コア・シェルから固体溶液構造への構造的変容を調査する.
- 合成されたPd-Pt固体溶液ナノ粒子の水素貯蔵能力を評価する.
主な方法:
- コア (Pd) /シェル (Pt) ナノ粒子の合成.
- 水素吸収/脱吸収サイクルによる構造変化を誘発する.
- インサイト粉末X線 difraktion,エネルギー分散スペクトル,固体状態 (2) H NMR,水素圧力組成イソテルムを用いた特徴付け.
主要な成果:
- 固体溶液ナノ粒子で達成されたPdとPtの均質な原子混合.
- 複数の高度な特徴付け技術によって確認された構造的変容.
- 固体溶液のPd-Ptナノ粒子 (8-21原子% Pt) は,純粋なPdナノ粒子よりも高い水素貯蔵容量を示した.
- 水素貯蔵容量は,PdとPtの組成を調整することで調節可能でした.
結論:
- 水素の吸収/分解は,Pd-Pt固体溶液ナノ粒子を作るのに有効なトリガーです.
- その結果生成されるPd-Pt固体溶液ナノ粒子は,従来のコアシェル構造と比較して優れた水素貯蔵性能を提供します.
- 調節可能な組成により,Pd-Pt合金ナノ粒子の水素貯蔵性能を最適化できます.
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