1ナノメートルの厚さのPtNiRhトリメタリックナノワイヤと強化された酸素還元電気触媒:複数の利点を一つの触媒に統合する
Kan Li1, Xingxing Li1, Hongwen Huang1,2
1Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Strongly-Coupled Quantum Matter Physics of Chinese Academy of Sciences, Department of Chemical Physics , University of Science and Technology of China , Hefei , Anhui 230026 , P. R. China.
Journal of the American Chemical Society
|November 3, 2018
まとめ
新しいプラチナ・ニッケル・ロジウム (PtNiRh) 三金属ナノワイヤ触媒の開発により,燃料電池における酸性酸素還元反応 (ORR) の活性と耐久性が著しく向上します.
科学分野:
- 材料科学
- 電気化学
- カタリシス
背景:
- 酸素還元反応 (ORR) は燃料電池の性能にとって極めて重要です.
- 酸性ORR触媒で高い活性と耐久性の両方を達成することは困難です.
- 現在の商用触媒であるプラチナ・オン・カーボン (Pt/C) には限界があります.
研究 の 目的:
- 酸性酸素還元反応 (ORR) の活性で耐久的な触媒を設計し合成する.
- 触媒性能の向上に貢献する構造的および組成的要因を調査する.
- 先進的な異質な触媒の開発のためのガイドラインを提供すること.
主な方法:
- 炭素 (PtNiRh/C) に支えられた1nm厚さのプラチナ・ニッケル・ロジウム (PtNiRh) の三金属ナノワイヤの合成.
- 触媒の質量活動とORRの特異性の電気化学的特徴
- 酸性条件下での触媒耐久性の評価
- 触媒特性に対する微細構造的および組成的効果の分析
主要な成果:
- PtNiRh/C触媒は,商用Pt/Cと比較して15.2倍以上の質量活性と9.7倍以上の特異活性を示した.
- 強化された活動は,ナノワイヤの微細構造と組成から圧縮ストレンスとリガンド効果に起因する.
- PtNiRh/C触媒は,商用Pt/Cよりも耐久性が著しく向上した.
- 耐久性の利点は一次元ナノワイヤ構造とロジウム (Rh) の組み込みから生じる.
結論:
- 複数の構造と組成上の利点を単一の触媒に統合することは,高い活性と耐久性を達成するのに有効です.
- PtNiRh三金属ナノワイヤは,酸性酸素還元反応の有望な触媒である.
- この研究は,エネルギーアプリケーションのための優れた異質な触媒の設計のための枠組みを提供します.
関連する概念動画
01:17Carboxylic Acids to Primary Alcohols: Hydride Reduction
5.0K
Carboxylic acids, upon reaction with strong reducing agents such as lithium aluminum hydride followed by hydrolysis, undergo reduction to form primary alcohols.
5.0K
01:19Acid Halides to Alcohols: LiAlH4 Reduction
4.0K
Acid halides are reduced to alcohols in the presence of a strong reducing agent like lithium aluminum hydride.
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
The mechanism proceeds in three steps. First, the nucleophilic hydride ion attacks the carbonyl carbon of the acid halide to form a tetrahedral intermediate. Next, the carbonyl group is re-formed, and the halide ion departs as a leaving group, generating an aldehyde. A second nucleophilic attack by the hydride yields an alkoxide ion, which, upon protonation, gives a primary alcohol as...
4.0K
03:11Oxidation-Reduction Reactions
75.7K
Oxidation–Reduction Reactions
75.7K
01:49Multiple Allele Traits
38.1K
The Concept of Multiple Allelism
38.1K
02:33Lewis Acids and Bases
48.4K
In 1923, G. N. Lewis proposed a generalized definition of acid-base behavior in which acids and bases are identified by their ability to accept or to donate a pair of electrons and form a coordinate covalent bond.
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...
48.4K
03:42Amino acids
105.5K
Amino acids are the monomers that comprise proteins. Each amino acid has the same fundamental structure, which consists of a central carbon atom, or the alpha (α) carbon, bonded to an amino group (NH2), a carboxyl group (COOH), and to a hydrogen atom. Every amino acid also has another atom or group of atoms bonded to the central atom known as the R group. There are 20 common amino acids present in proteins, each with a different R group. Variation in the amino acid sequence is responsible for...
105.5K