通过微孔重新审视离子运输:显著且不可忽视的表面运输
Wenchang Zhang1, Ao Zhang2, Wenzhe Zhou1
1Institute of Applied Physics and Materials Engineering, University of Macau, Macau SAR 999078, P. R. China. pengzhansun@um.edu.mo.
Nanoscale horizons
|December 24, 2025
概括
表面导电在较大的化孔中显著影响离子运输,甚至在稀释溶液中占主导地位. 这一发现为微孔系统开辟了新的技术可能性.
科学领域:
- 物理化学 物理化学
- 材料科学 材料科学 材料科学
- 纳米技术纳米技术
背景情况:
- 孔中的离子运输通常使用散装导电性进行建模,假设表面效应是可以忽略不计的.
- 理论模型预测表面导电在稀释溶液中变得很重要,特别是在纳米孔中.
- 在较大的 (微) 孔中缺乏显著表面导电的实验证据.
研究的目的:
- 通过实验研究表面导电在通过化微孔的离子传输中的作用.
- 为了确定表面导电是否可以在比纳米孔更大的毛孔中显著.
- 探索增强微孔表面导电的方法.
主要方法:
- 电气测量通过化孔的离子传输,直径从亚微米到几微米.
- 溶液度的系统变化,低至1毫米.
- 用二维材料 (石墨烯,石墨烯氧化物,) 修改毛孔表面.
主要成果:
- 在化微孔中,表面导电被发现是显著且不可忽视的,特别是在低于1毫米的度下.
- 观察到的表面导电性 (约1nS) 在稀释溶液中占据主导地位,导致大杜金长度和数量.
- 用二维材料覆盖毛孔表面,可以提高表面导电率1到2个数量级,并取决于度.
结论:
- 表面导电在通过化微孔的离子传输中起着至关重要的作用,这与传统的假设相反.
- 这些发现挑战了表面导电仅限于纳米孔的概念.
- 在微孔中增强的表面导电性为以前仅限于纳米孔系统的新技术应用提供了潜力.
相关概念视频
The Significance of Membrane Transport
40.9K
The transport of solutes across the cell membrane is essential for metabolic processes, like maintaining cell size and volume, generating the action potential, exchanging nutrients and gases, etc. Membrane transport can be either passive or active. It can be simple diffusion, facilitated, or mediated transport aided by transport proteins such as transporters and channels.
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...
40.9K
Pore Transport and Ion-Pair Transport
1.1K
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...
1.1K
Facilitated Diffusion
1.1K
The plasma membrane, a critical structure in cellular biology, houses an array of transporters, or carrier proteins, interspersed within its lipid bilayer. These proteins play a crucial role in solute transport through facilitated diffusion, a form of passive diffusion that uses transporters to move the molecules across the membrane.
In this process, substrates such as organic compounds and ions interact with a transporter on one side, triggering conformational changes in proteins that enable...
In this process, substrates such as organic compounds and ions interact with a transporter on one side, triggering conformational changes in proteins that enable...
1.1K
Facilitated Transport
18.0K
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...
18.0K
Facilitated Transport
145.5K
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...
145.5K
Carrier-Mediated Transport
975
Carrier-mediated transport is a pivotal process in drug absorption, particularly for lipid-insoluble drugs, and encompasses facilitated diffusion and active transport. Facilitated diffusion allows drugs to move along their concentration gradient without energy expenditure, while active transport utilizes ATP to drive drug movement against this gradient.
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
Active transport involves two types of membrane-spanning transporters: uptake and efflux. Uptake transporters are expressed in the small...
975


