交流阻抗模拟软件的应用Zview

1、Analysis of electrochemical impedance spectra (EIS) Reporter: LingChenMar. 3rd 20062Introduction of EIS Electrochemical impedance spectroscopy (EIS) is a very powerful tool to analyze the electrochemical electrode reactions and has been commonly used to analyze the electrochemical interface. Impedan

2、ce spectrums are often modeled using an electrical circuit which produces a similar spectrum. The electrical components (resistors, capacitors, inductors, etc) and some components that have no electrical analog (constant phase elements, Warburg impedances, etc) are then matched to physical character

3、istics of the measured cell.3Outline 1.Fit by Zview Software 2.Data preparation 3.Examples41. Fit by Zview1.1 Circle Fit The semi-circle fit is a geometric fit not an RC or Equivalent Circuit fit. 5 One method of producing initial values1. Fit by Zview1.2 Instant FitCPE = Constant Phase ElementParam

4、eters: CPE-T, CPE-PZ = 1 / T(i)PCPE-P = 0.5a 45 degree lineCPE-P = 1a capacitorOften a CPE is used in a model in place of a capacitor to compensate for non-homogeneity in the system.61. Fit by Zview1.3 Equivalent Circuits Fit71.4 Examples Example 1 Example 282.1 Experiment results Z Z f p f Z2.Data

5、preparation92.2 Data TransformationFrequency(Hz)Z (Real)Z (imaginary)IZIphase+-+-0.011167.99-78.66521170.64-0.853090.013141149.63-66.58611151.56-3.31484760954.00774-0.641234.05871-9.090171000003.91905-0.423823.9419-6.17213The data is transformed to ASCII form by Origin software2.Data preparation10Example11Summarization We must rely on our own knowledge of the physical system we are measuring. It can also be helpful to see if the model gives “reasonable” values. Real experimental data is usually hard