溶剤フリーコーディネティブウレア挿入による金属有機フレームワークにおける超プロトン伝導
Marvin K Sarango-Ramírez1, Dae-Woon Lim1, Daniil I Kolokolov2,3
1Division of Chemistry, Graduate School of Science, Kyoto University, Kitashirakawa-Oiwakecho, Sakyo-ku, Kyoto 606-8502, Japan.
Journal of the American Chemical Society
|March 13, 2020
まとめ
研究者は,溶媒のない尿素挿入を用いて,MOF-74で高プロトン伝導性を達成した. この方法は水素結合を強化し,酸性成分なしで性能を改善するために材料の性質を変更します.
科学分野:
- 材料科学
- 固体化学
- プロトン伝導
背景:
- MOF-74のようなメタル・オーガニック・フレームワーク (MOF) は,様々な用途の調整可能な構造を提供します.
- 固体材料で高プロトン伝導性を達成することは エネルギー装置にとって極めて重要です
- 既存の方法はしばしば酸性成分または溶媒を必要とし,実用的な応用を制限しています.
研究 の 目的:
- MOF-74の陽子の伝導性を高めるための新しい溶媒のない方法を開発する.
- 尿素の挿入によって促進される陽子輸送のメカニズムを調査する.
- 酸性成分のないMOFで高い安定した超プロトン伝導性を実証する.
主な方法:
- MOF-74 (Ni2+とMg2+を基に) に溶媒のない,調整性尿素を挿入する.
- 改造されたMOFの構造と性質の特徴
- 陽子の拡散を研究するための固体2H核磁気共振 (NMR) スペクトロスコーピー.
主要な成果:
- 非常に安定した超陽子伝導率 (> 10−2 S cm−1) を達成した.
- 尿素の挿入により,空洞の体積と表面の機能が変化し,陽子の輸送に影響を及ぼした.
- H NMRは,水と極化尿素の間の強化された水素結合を明らかにし,陽子の拡散を促進しました.
結論:
- 溶媒のない尿素の挿入は,MOF-74の陽子伝導性を高めるための効果的な戦略です.
- このメカニズムは,金属部位に尿素を調整し,フレームワークを変更し,陽子輸送のための水素結合を強化します.
- このアプローチは,電気化学アプリケーションのための先進的な陽子伝導材料の開発に有望な経路を提供します.
関連する概念動画
02:51Metal-Ligand Bonds
23.5K
The hemoglobin in the blood, the chlorophyll in green plants, vitamin B-12, and the catalyst used in the manufacture of polyethylene all contain coordination compounds. Ions of the metals, especially the transition metals, are likely to form complexes.
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
In these complexes, transition metals form coordinate covalent bonds, a kind of Lewis acid-base interaction in which both of the electrons in the bond are contributed by a donor (Lewis base) to an electron acceptor (Lewis acid). The Lewis acid in...
23.5K
02:42Valence Bond Theory
10.9K
Coordination compounds and complexes exhibit different colors, geometries, and magnetic behavior, depending on the metal atom/ion and ligands from which they are composed. In an attempt to explain the bonding and structure of coordination complexes, Linus Pauling proposed the valence bond theory, or VBT, using the concepts of hybridization and the overlapping of the atomic orbitals. According to VBT, the central metal atom or ion (Lewis acid) hybridizes to provide empty orbitals of suitable...
10.9K
02:54Coordination Compounds and Nomenclature
25.8K
In most main group element compounds, the valence electrons of the isolated atoms combine to form chemical bonds that satisfy the octet rule. For instance, the four valence electrons of carbon overlap with electrons from four hydrogen atoms to form CH4. The one valence electron leaves sodium and adds to the seven valence electrons of chlorine to form the ionic formula unit NaCl (Figure 1a). Transition metals do not normally bond in this fashion. They primarily form coordinate covalent bonds, a...
25.8K
02:34Structural Isomerism
21.4K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
Isomers are different chemical species that have the same chemical formula. Structural isomerism of coordination compounds can be divided into two subcategories, the linkage isomers and coordination-sphere isomers.
Linkage isomers occur when the coordination compound contains a ligand that can bind to the transition metal center through two different atoms. For example, the CN− ligand can bind through the carbon atom or through the nitrogen atom. Similarly, SCN− can...
21.4K
03:45Formation of Complex Ions
25.5K
A type of Lewis acid-base chemistry involves the formation of a complex ion (or a coordination complex) comprising a central atom, typically a transition metal cation, surrounded by ions or molecules called ligands. These ligands can be neutral molecules like H2O or NH3, or ions such as CN− or OH−. Often, the ligands act as Lewis bases, donating a pair of electrons to the central atom. These types of Lewis acid-base reactions are examples of a broad subdiscipline called coordination...
25.5K
02:58Crystal Field Theory - Octahedral Complexes
30.1K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
30.1K