调整Zn站点的协调结构通过对称性破坏加速电催化
Yuntong Sun1, Wenjun Fan2, Yinghao Li1
1School of Chemistry, Chemical Engineering and Biotechnology, Nanyang Technological University, 62 Nanyang Drive, Singapore, 637459, Singapore.
Advanced materials (Deerfield Beach, Fla.)
|August 30, 2023
概括
在金属有机框架 (Zn-MOFs) 中的对称性破坏优化了电催化剂的活性位点. 这种设计增强了 (N2) 减少反应 (NRR),提高了氨生产效率.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 精确控制活动地点协调环境对于高效的电催化反应至关重要.
- 设计具有量身定制的协调微环境的催化剂仍然是一个重大挑战.
研究的目的:
- 合成具有明确结构的破坏对称性的金属有机框架 (Zn-MOF) 催化剂.
- 调查优化协调微环境对电催化性能的影响,特别是对于降解反应 (NRR).
主要方法:
- 基于理论预测,轻松合成破坏对称性的Zn-MOFs.
- 对NRR合成的催化剂进行电催化测试.
- 射线吸收近边结构 (XANES) 谱学分析电子结构.
- 理论计算 (例如,DFT) 来阐明反应机制.
主要成果:
- 一系列破坏对称性的Zn-MOFs被成功合成.
- Zn-N2S2-MOF催化剂表现出优越的NRR性能,NH3产率为25.07 ± 1.57 μg h−1 cm−2和法拉第克效率为44.57 ± 2.79%.
- XANES和理论计算显示,对称性破坏调节电子分布,有利于低价值Znδ+物种,通过降低能量屏障来促进N2吸附和激活.
结论:
- 该研究确立了金属站点的精确协调环境与电催化活性之间的明确联系.
- 在Zn-MOF中破坏对称性是设计高性能NRR电催化剂的有效策略.
- 这项工作为各种反应的先进电催化剂的合理设计提供了宝贵的见解.
更多相关视频
04:51Author Spotlight: Functionalizing Metal-Organic Frameworks: Advancements, Challenges, and the Power of Post-Synthetic Ligand Exchange
Published on: June 23, 2023
3.0K
05:47Preparation of Polyoxometalate-based Photo-responsive Membranes for the Photo-activation of Manganese Oxide Catalysts
Published on: August 7, 2018
7.7K
相关概念视频
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
42.9K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
42.9K
02:42Valence Bond Theory
8.7K
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...
8.7K
02:58Crystal Field Theory - Octahedral Complexes
26.7K
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...
26.7K
02:57Coordination Number and Geometry
16.0K
For transition metal complexes, the coordination number determines the geometry around the central metal ion. Table 1 compares coordination numbers to molecular geometry. The most common structures of the complexes in coordination compounds are octahedral, tetrahedral, and square planar.
16.0K
01:48ATP Synthase: Mechanism
14.8K
In animals, the mitochondrial F1F0 ATP synthase is the key protein that synthesizes ATP molecules through a complex catalytic mechanism. While the nuclear genome encodes the majority of ATP synthase subunits, the mitochondrial genome encodes some of the enzyme's most critical components. The formation of this multi-subunit enzyme is a complex multi-step process regulated at the level of transcription, translation, and assembly. Defects in one or more of these steps can result in decreased...
14.8K
03:45Formation of Complex Ions
23.7K
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...
23.7K