Title: A Comparison between Surface Potential and Electrochemical Potentials
Introduction
Surface potential and electrochemical potentials are two physical variables that depict the energy of molecules at the surface of surfaces and within electrodes, respectively. So in some sense, they measure the same physical phenomena. However, they are used in different ways to understand the energy of systems. This paper will explore the differences between surface potential and electrochemical potentials, and their differences in application.
What are Surface Potentials?
Surface potential is a measure of the charge located on a surface. It is determined by the electron density distribution of the material which is forming the surface. This electron density can be manipulated with the use of a charged surface, where the excess of electrons (or lack thereof) influences the surface potential.
What are Electrochemical Potentials?
Electrochemical potentials measure the energy of molecules which are in electric fields. When they are in electric fields, molecules are electrostatically charged and therefore have an associated energy. This energy can be measured by applying an external electric field, which causes the molecules to move in or out of the field, depending on their charge.
Differences between Surface Potential and Electrochemical Potentials
A key difference between surface potential and electrochemical potentials is that surface potential is relatively static, whereas electrochemical potentials are more dynamic. While the surface potential is unaffected by electric fields, the electrochemical potentials can be manipulated by changing the external electric field.
Another difference between surface potential and electrochemical potentials is that surface potentials represent the state of an entire surface, whereas electrochemical potentials represent the energy of molecules within an electric field. For example, a molecule in a cylindrical electric field may still be affected by the electric field even though the majority of the surface is free of electric fields.
In terms of application, surface potentials can typically be used to study the properties of surfaces, such as charge distribution, shielding effects and electric field inhomogeneity. On the other hand, electrochemical potentials are mainly used to study the behavior of molecules within electric fields.
Conclusion
Surface potential and electrochemical potentials are two physical variables that describe the energy of molecules at the surface of surfaces and within electrodes, respectively. Both measure the same physical phenomena, however they have different characteristics and main applications. Surface potentials are relatively static and used to study the properties of surfaces, whereas electrochemical potentials are more dynamic and mainly used to study the behavior of molecules in electric fields.
