コンパクト金属のアンミン塩の間接的,可逆的な高密度水素貯蔵
Rasmus Z Sørensen1, Jens S Hummelshøj, Asbjørn Klerke
1Center for Sustainable and Green Chemistry, Department of Chemistry, Building 206, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark.
Journal of the American Chemical Society
|June 14, 2008
まとめ
Ca ((NH3) 8Cl2のような金属アンミン塩化物は,高容量の間接的な水素貯蔵を提供する. これらの材料は,アンモニア (NH3) と水素 (H2) を迅速に放出し,水素貯蔵の応用の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
- 化学工学は化学工学というものです.
- 水素貯蔵技術について
背景:
- 効率的な水素貯蔵材料の開発は,クリーンエネルギー技術の進歩に不可欠です.
- 金属アンミン塩化物は,高い水素含有量があるため,間接的な水素貯蔵のための有望な道を示しています.
研究 の 目的:
- Mg ((NH3) 6Cl2,Ca ((NH3) 8Cl2,Mn ((NH3) 6Cl2,Ni ((NH3) 6Cl2) の間接的な水素貯蔵可能性を調査する.
- アンモニア (NH3) と水素 (H2) を分析するには,これらの金属アンミン塩化物から放出運動とメカニズムを分析します.
主な方法:
- 金属アンミン塩化物を圧縮して密度の高い固体錠剤にします.
- 温度プログラムドソープション (TPD) を使って,異なる加熱速度でNH3の放出を研究する.
- 密度関数理論 (DFT) の計算を用いて,解吸収エンタルピーとメカニズムをモデル化します.
主要な成果:
- 4つの金属アンミン塩化物すべては,圧縮されたときに高密度 (>95%の結晶密度) を達成しました.
- Ca(NH3) 8Cl2は,かなりの水素貯蔵能力 (最大9.78重 % H,0.116kg H/L) を示した.
- NH3の脱吸収は主に熱伝導に制限され,急速な運動性を示し,ナノ孔構造はMg (NH3) 6Cl2,Mn (NH3) 6Cl2,Ni (NH3) 6Cl2) で脱吸収を促進する.
結論:
- 金属アンミン塩化物は,間接的な水素貯蔵に有効な材料であり,高重度および体積密度を提供します.
- 急速な吸収解消運動は,熱伝送の制限とナノ孔状構造の形成に起因する.
- DFTの計算は,素早い水素吸収/脱吸収サイクルのための表面連鎖放出メカニズムをサポートしています.
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