交流阻抗的分析？扩散电阻，专著或者教科书上叫浓差阻抗。通俗一点讲就是指活性物质(反应物或者生成物)对电极反应造成在阻碍（及阻抗）。浓差扩散阻抗有电阻Z(R)和电容 Z(C）组成。Zw=Z(R)+ Z(C）=Rw - (1/ωC)jZw即通常所说的Warburg阻抗，其中Z(R)=σ/[ω(1/2)]，Z(C)=1/[σ*ω(1/2)]σ是Warburg系数。在EIS图谱的复平面中，Warburg阻抗是与实轴成45°角的直线，阻抗大小与频率有关。英文的解释如下：The Warburg diffusion element is a common diffusion circuit element that can be used to model semi-infinite linear diffusion, that is, unrestricted diffusion to a large planar electrode. A Warburg impedance element can be difficult to recognize because it is nearly always associated with a charge-transfer resistance (see charge transfer complex) and a double layer capacitance (see double layer (interfacial)), but is common in many systems.The Warburg diffusion element (ZW) is a constant phase element (CPE), with a constant phase of 45° (phase independent of frequency) and with a magnitude inversely proportional to the square root of the frequency by:Zw=σ(1-j)/[ω(1/2)]|Zw|=σ*[2(1/2)]/[ω(1/2)]where σ is the Warburg coefficient (or Warburg constant), j is the imaginary number and ω is the angular frequency. The presence of the Warburg element can be recognised if a linear relationship on the log of a Bode plot (log|Z| versus log(w)) exists with a slope of value –1/2，查看更多
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