脱水したプルーシアンブルーのアナログM3[Co(CN) [6]2 (M = Mn, Fe, Co, Ni, Cu, Zn) で水素貯蔵
Steven S Kaye1, Jeffrey R Long
1Department of Chemistry, University of California, Berkeley, CA 94720-1460, USA.
Journal of the American Chemical Society
|May 5, 2005
まとめ
プルーシアンブルーの類型は,表面積が大きく,水素貯蔵能力が大きい. これらの材料は,効率的な水素吸附および貯蔵アプリケーションの有望な可能性を示しています.
科学分野:
- マテリアルサイエンス 材料科学
- 化学 化学は化学です.
- ナノテクノロジー ナノテクノロジー
背景:
- プルーシアンブルーの類型は,調節可能な構造を持つ調整化合物です.
- 効率的な水素貯蔵材料は,クリーンエネルギー技術にとって極めて重要です.
- 毛細度と吸収特性を理解することは,材料設計の鍵です.
研究 の 目的:
- 脱水したプルーシアンブルーの類似体M3[Co(CN) ]2.6の多孔性と水素貯蔵性能を調査する.
- これらの材料が冷凍温度で水素を吸収する可能性を評価する.
- 材料の組成と水素の吸収の関係を見極めるため.
主な方法:
- プルーシアンブルーの6種類の同種:M3[Co(CN) [6]2 (M = Mn, Fe, Co, Ni, Cu, Zn) を合成した.
- BET表面積を決定するために87Kのアルゴンソープションイソテルム.
- 貯蔵容量を測定するために,77 K と 890 Torr の水素吸収同温器.
- 最大吸収予測のためのラングミュア-フリードリヒ方程式のフィッティング.
- 77 K. と 87 K. の水素イソテルムから吸収エンタルピーを計算する.
主要な成果:
- BETの表面積は560 m2/g (Ni) から870 m2/g (Mn) までの範囲で,Mn3[Co(CN) [6]2はゼオライトに匹敵する.
- 重要な水素吸収が観察され,容量は最大1.8%重量%と0.025kgH2/L (Cu) であった.
- 予想される飽和能力は,Cu3[Co(CN) [6]の2.1重量%と0.029kgH2/Lに達した2.
- アドソルプションエンタルピーはMと共にM
結論:
- 脱水したプルーシアンブルーの類型は,表面積が大きく,水素貯蔵能力が大きい.
- 研究された材料は,ベンチマークの金属有機フレームワークと比較して優れた結合エンタルピーを示しています.
- これらの発見は,先進的な水素貯蔵ソリューションの有望な候補として,プルーシアンブルーの類似性を強調しています.
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