Polarisierungskurven

Polarisierungskurven, also known as polarization curves or Tafel plots, are graphical representations used in electrochemistry to study the behavior of electrochemical cells. They plot the logarithm of current density against the applied potential. This type of plot is particularly useful for understanding the kinetics of electrode reactions.

When current flows through an electrochemical cell, the potential deviates from its equilibrium value due to various factors such as charge transfer resistance, mass transport limitations, and ohmic resistance. Polarisationskurven help to separate and analyze these contributions. The linear portion of the polarization curve, often observed at higher current densities, is known as the Tafel region. In this region, the relationship between the logarithm of the current density and the potential is approximately linear, following the Tafel equation.

The slope of the Tafel region provides valuable information about the electrochemical reaction mechanism, specifically the transfer coefficient and the rate constant. By examining the shape and slope of the polarization curve, researchers can identify limiting steps in the reaction, determine activation energies, and compare the performance of different electrode materials or electrolytes. They are essential tools in fields like corrosion science, battery research, fuel cell development, and electroplating.