水素貯蔵のための触媒水素の溢出
1Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, USA. yang@umich.edu
Journal of the American Chemical Society
|March 3, 2009
まとめ
TiCl ((3)) またはVCl ((3) を含んだ炭ソーベンツのドーピングは,水素貯蔵率を大幅に高めます. このブレークスルーは,輸送用燃料電池のための水素経済の開発における主要な課題に取り組んでいます.
科学分野:
- 材料科学 材料科学とは
- 化学工学は化学工学というものです.
- エネルギー貯蔵 エネルギー貯蔵
背景:
- 水素貯蔵は,特に燃料電池車では,水素経済にとって非常に重要です.
- 現在の水素貯蔵方法は,容量と充電/放電率に関する課題に直面しています.
- 吸収剤材料における水素の溢出は有望だが,速度が遅れている.
研究 の 目的:
- 吸収剤材料における水素の溢出率を改善するための方法を調査する.
- 水素アドソルプションとデソルプションの動力学に対する金属塩ドーピングの影響を評価する.
- ドーピングが水素結合エネルギーとイソサーム特性に及ぼす影響を分析する.
主な方法:
- チタン (III) クロリド (TiCl) とバナジウム (III) クロリド (VCl) を用いたドーピングされたソーベンツ材料の合成.
- 水素アドソルプションとデソルプションの速度を体積法で測定する.
- ヒステレスと熱力学的パラメータを決定するために,水素イソテルマの分析.
- 溢出プロセスの吸附熱と活性化エネルギーの計算.
主要な成果:
- 2 wt % TiCl ((3) または VCl ((3) を使ったドーピングは,水素吸収と脱吸収率を著しく増加させた.
- 水素イソサーマにおけるヒステレスループは,ドーピングによって排除された.
- 吸収熱と溢出のための活性化エネルギーは,ドーピングで減少しました.
- ドーピングは,溢れた水素と炭素表面の間の結合エネルギーを低下させた.
結論:
- 金属塩のドーピングは,吸収物質の水素溢出運動を高めるための効果的な戦略です.
- 低結合エネルギーは,燃料電池アプリケーションにおいて極めて重要な,より速い水素吸収と放出を促進します.
- このアプローチは,機内水素貯蔵に関する米国エネルギー省の目標を達成するための道筋を提供します.
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