アニオン交換膜燃料電池のための効率的なNH3耐性ニッケルベースの水素酸化触媒
Ye-Hua Wang1, Fei-Yue Gao1, Xiao-Long Zhang1
1Division of Nanomaterials & Chemistry, Hefei National Laboratory for Physical Sciences at the Microscale, Department of Chemistry, University of Science and Technology of China, Hefei 230026, China.
Journal of the American Chemical Society
|August 1, 2023
まとめ
この研究では,燃料電池におけるアンモニア中毒に対する高い耐性を示すクロム添加ニッケルモリブデン合金 (Cr-MoNi4) の新しい触媒を導入した. この進歩により,より純粋な水素で効率的な水素燃料電池操作が可能になり,性能と耐久性が向上します.
科学分野:
- 電気化学
- 材料科学
- カタリシス
背景:
- 燃料電池は水素を効率的に電気に変換しますが,超純水素が必要です.
- アンモニア (NH3) と他の不純物は,炭素 (Pt/C) 触媒の従来のプラチナを汚染し,燃料電池の性能を低下させます.
- 水素燃料電池の実用的な応用には,不純物への耐性のある強固な触媒の開発が不可欠です.
研究 の 目的:
- 水素燃料電池のアンモニア抵抗性を高める新しい触媒を開発する.
- 塩基媒介におけるクロム添加ニッケルモリブデン合金 (Cr-MoNi4) の触媒活性と耐久性を調査する.
- 新しい触媒のアンモニア耐性の背後にあるメカニズムを解明する.
主な方法:
- クロミウムドープされたニッケルモリブデン合金 (Cr-MoNi4) の合成と特徴付け.
- アルカリ水素酸化反応における触媒活性と耐久性の電気化学試験
- アンモニアで汚染された水素条件下での燃料電池性能評価
- アンモニア吸収機構を理解するための密度機能理論 (DFT) の計算.
主要な成果:
- Cr-MoNi4触媒はアルカリ水素酸化に高い活性を示した.
- 触媒は2ppmのアンモニアで1万回のサイクルで活動を維持した.
- Cr-MoNi4を使用した燃料電池は,Pt/Cの61%と比較して,10ppmのアンモニアでピーク電力密度の95%を保持しました.
- 理論的研究によると,クロムドーピングは電子特性を変えてアンモニア吸収を弱める.
結論:
- クロミウム添加ニッケルモリブデン合金 (Cr-MoNi4) は,従来のPt/C触媒と比較して優れているアンモニア抵抗性を示す.
- アンモニアの存在下での耐久性と性能の向上により,Cr-MoNi4は実用的な水素燃料電池の有望な候補となります.
- クロミウムによる電子調節は,アンモニア中毒を抑制し,より純粋な水素源の使用への道を開くための鍵です.
さらに関連する動画
関連する概念動画
Reduction of Alkenes: Asymmetric Catalytic Hydrogenation
3.4K
Catalytic hydrogenation of alkenes is a transition-metal catalyzed reduction of the double bond using molecular hydrogen to give alkanes. The mode of hydrogen addition follows syn stereochemistry.
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
The metal catalyst used can be either heterogeneous or homogeneous. When hydrogenation of an alkene generates a chiral center, a pair of enantiomeric products is expected to form. However, an enantiomeric excess of one of the products can be facilitated using an enantioselective reaction or an...
3.4K
Catalysis
27.0K
The presence of a catalyst affects the rate of a chemical reaction. A catalyst is a substance that can increase the reaction rate without being consumed during the process. A basic comprehension of a catalysts’ role during chemical reactions can be understood from the concept of reaction mechanisms and energy diagrams.
27.0K
Reduction of Alkenes: Catalytic Hydrogenation
12.2K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
12.2K
Batteries and Fuel Cells
27.6K
A battery is a galvanic cell that is used as a source of electrical power for specific applications. Modern batteries exist in a multitude of forms to accommodate various applications, from tiny button batteries such as those that power wristwatches to the very large batteries used to supply backup energy to municipal power grids. Some batteries are designed for single-use applications and cannot be recharged (primary cells), while others are based on conveniently reversible cell reactions that...
27.6K
Ion Exchange
622
Ion exchange chromatography separates charged molecules from a solution by reversibly exchanging them with mobile, or 'active', ions associated with the oppositely charged stationary phase. This method can be used to separate ions, soften and deionize water, and purify solutions. The polymers comprising the ion-exchange column are high-molecular-weight and chemically stable polymers, crosslinked to be porous and essentially insoluble. They are also functionalized with either acidic or...
622


