选择性蒸汽压力依赖性质子传输在具有两个明显的水友孔的金属有机框架中
Sarah S Park1, Adam J Rieth1, Christopher H Hendon1
1Department of Chemistry, Massachusetts Institute of Technology , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
Journal of the American Chemical Society
|February 3, 2018
概括
研究人员研究了金属有机框架中的质子导电性, MIT-25揭示了两个不同的运输途径. 这一发现有助于我们更好地理解多孔材料中的质子导电.
科学领域:
- 材料科学
- 化学学
- 物理
背景情况:
- 在多孔固体中的质子导电性对于能源应用至关重要.
- 由于许多导体的无形性,理解孔隙结构和质子传输机制之间的关系是具有挑战性的.
- 金属有机框架 (MOF) 为研究这些现象提供可调节的多孔结构.
研究的目的:
- 在MIT-25中系统地阐明不同质子传输途径.
- 将特定的孔隙结构和充填动力学与质子导电机制相关联.
- 在不同尺寸的平行通道中区分质子运输行为.
主要方法:
- 使用温度和湿度依赖的质子导电性测量.
- 用密度函数理论 (DFT) 计算进行理论洞察.
- 控制蒸汽压力以连续填充不同大小的孔隙 (∼27 Å和∼4.5 Å).
主要成果:
- 在MIT-25的平行通道内确定了两个不同的质子运输途径.
- 在相对湿度低和高时观察到不同质子导电的激活能量,这与连续的孔隙填充相对应.
- 证明了孔径大小和水分水平对质子运输机制的影响.
结论:
- MIT-25表现出不同的质子导电机制,取决于孔隙填充和相对湿度.
- 这项研究提供了一种系统的方法来理解多孔质子导体中的结构功能关系.
- 这些发现有助于合理设计用于质子导电的先进材料.
更多相关视频
相关概念视频
Vapor Pressure
41.1K
When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor...
41.1K
Vapor Pressure Lowering
31.5K
The equilibrium vapor pressure of a liquid is the pressure exerted by its gaseous phase when vaporization and condensation are occurring at equal rates:
31.5K
Pore Transport and Ion-Pair Transport
1.3K
Pore transport and ion-pair formation are critical mechanisms for the absorption and distribution of drugs in the body.
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct...
Pore transport, also known as convective transport, is a process where small molecules like urea, water, and sugars rapidly cross cell membranes as though there were channels or pores in the membrane. Although direct microscopic evidence is limited but the concept of pores or channels is widely accepted based on physiological evidence. Despite the lack of direct...
1.3K
Frequency-dependent Selection
24.2K
When the fitness of a trait is influenced by how common it is (i.e., its frequency) relative to different traits within a population, this is referred to as frequency-dependent selection. Frequency-dependent selection may occur between species or within a single species. This type of selection can either be positive—with more common phenotypes having higher fitness—or negative, with rarer phenotypes conferring increased fitness.
24.2K
Vapor Pressure of Fluid
2.0K
The vapor pressure of a fluid is a crucial concept in fluid mechanics, influencing phenomena such as boiling and cavitation. Vapor pressure refers to the pressure exerted by a vapor at a state of thermodynamic equilibrium with its corresponding liquid phase at a specific temperature. It represents the tendency of molecules to escape from the fluid surface into the vapor phase.
When a liquid is placed in a closed container with a small air space, and the space is evacuated, vapor molecules will...
When a liquid is placed in a closed container with a small air space, and the space is evacuated, vapor molecules will...
2.0K
Facilitated Transport
152.1K
The chemical and physical properties of plasma membranes cause them to be selectively permeable. Since plasma membranes have both hydrophobic and hydrophilic regions, substances need to be able to transverse both regions. The hydrophobic area of membranes repels substances such as charged ions. Therefore, such substances need special membrane proteins to cross a membrane successfully. In facilitated transport, also known as facilitated diffusion, molecules and ions travel across a...
152.1K


