在离子液和水溶液中的石墨烯中,电化学门控制的电荷传输
Fang Chen1, Quan Qing, Jilin Xia
1Center for Bioelectronics and Biosensors, Biodesign Institute, Department of Electrical Engineering, Arizona State University, Tempe, Arizona 85287, USA.
Journal of the American Chemical Society
|July 4, 2009
概括
我们研究了溶液中的石墨烯晶体管. 杂质散射会影响导电性,而离子度会影响性能,这对于生物传感器的发展至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 表面科学是一门学科.
背景情况:
- 石墨烯晶体管对电子应用具有前景.
- 电化学门允许调节的载体度.
- 解决方案环境为设备性能带来了独特的挑战和机会.
研究的目的:
- 在各种溶液中研究电化学封闭的石墨烯晶体管的电子传输行为.
- 了解充电杂质和离子度对石墨烯导电性的影响.
- 探索这些设备在生物传感应用中的潜力.
主要方法:
- 石墨烯晶体管的电化学门.
- 在离子液体和水溶液中的测量.
- 导电性,载体密度和杂质度的分析.
- 对离子选效应的建模.
主要成果:
- 在离子液体中确定电子和孔载体密度.
- 估计的带电杂质度介于 (1-10) x 10^12 cm^-2.
- 观察到最小导电率的指数性下降随着杂质散射导致杂质密度的增加.
- 发现,随着水溶液中离子度的增加,最小导电率会变为负值.
结论:
- 杂质散射显著影响了石墨烯晶体管的导电性.
- 溶液中的离子度会屏蔽杂质,影响设备的性能.
- 了解这些传输特性对于开发基于石墨烯的生物传感器至关重要.
相关概念视频
The Electrical Double Layer
In the region where two bulk phases meet, an intricate electric charge distribution arises due to charge transfer, ion adsorption, molecular orientation, and charge distortion. This complex distribution is commonly referred to as the electrical double layer.When a solid electrode interfaces with ions in an electrolyte solution, the speed of electron transfer dictates the rates of oxidation and reduction. The electrode acquires a charge through the escape of atoms into the solution as cations or...
Transport Number
The transport number is the fraction of the total current carried by an ion in an electrolyte solution. It is defined as the ratio of the current carried by a specific ion to the total current flowing through the solution. The transport number, t, is central to understanding ionic mobility, which describes how fast an ion moves under the influence of an electric field. This link connects the physical behavior of ions in solution to the chemical processes that occur during electrochemical...
Electrochemical Systems
Electrochemical systems provide a fascinating insight into the dynamic interplay of charged species within various phases. One notable example is the interaction between a membrane permeable to K⁺ ions but not to Cl⁻ ions, separating an aqueous KCl solution from pure water. As K⁺ ions diffuse through the membrane, they generate net charges on each phase, leading to a potential difference between them.Similarly, when a piece of Zn is immersed in an aqueous ZnSO₄ solution, the Zn metal, composed...
Electrical Transport
The electrical transport property of a material is defined by its resistance and conductivity. Resistance is the measure of a material's ability to resist the flow of electric current, while conductivity gauges its ability to allow the current to pass through, depending on the geometry of the measurement cell, such as electrode spacing and area. Conductivity is measured in Siemens (S). There are different types of conductance, including specific conductance, equivalent conductance, and molar...
Debye–Huckel–Onsager Conductance Equation
The Debye-Hückel-Onsager equation is a cornerstone of physical chemistry, providing a method to determine the molar conductance (Λm) and molar conductance at infinite dilution (Λ°m) for uni-univalent electrolytes.Uni-univalent electrolytes are electrolytes that dissociate in solution to produce one cation with a +1 charge and one anion with a –1 charge per formula unit.This equation addresses two crucial phenomena: the asymmetry effect and the electrophoretic effect. According to this equation,...
Electrochemical Gradient and Channel Proteins: An Overview
An electrochemical gradient is a fundamental concept in biology and chemistry. It regulates the movement of ions across cell membranes. This movement is influenced by two factors:
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...
The electrical gradient: The electrical gradient across cell membranes refers to the difference in electric charge between the inside and outside of a cell. This difference drives the movement of ions towards or away from the cells. For instance, if the inside of the cell is more negatively charged relative to the...


