电化学阻抗谱分析方法【英文】

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电化学阻抗谱

波特图 Bode plot
log|Z|
/ deg
电化学系统的工作原理
阻抗~频率
锁相放大器频谱分析仪
交流伏安法
阻抗模量、相位角~频率
Eeq
电化学阻抗法
E=E 0sin(t)
阻抗测量技术
t
EIS测量的前提条件
因果性条件（causality）
输出的响应信号只是由输入的扰动信号引起的。
输出的响应信号与输入的扰动信号之间存在线性关系。电化学系统的
1 1 j C d Rct
型的EIS结果是“半圆+尾巴”的曲线，如下图所示：
0
R Rct / 2
等效电路：
R
Cd
ZW
阻抗是一个复数，可表示为实部 ZRe和虚部 ZIm两部分，
Rct
等效电路的阻抗：
因此，所得到的EIS谱图也是以这两部分为x，y轴。典
Z R
1 jCd 1 Rct 1/ 2 (1 j )
电组R和电容C并联的电路
并联电路的阻抗的倒数是各并联元件阻抗倒数之和
Z Z jZ
'
''
Nyquist 图上为半径为R/2的半圆
1 1 1 1 R R 2C jC j 2 Z Z R ZC R 1 (RC) 1 (RC) 2
实部：
R Z' 1 (RC) 2
虚部：
R 2C Z'' 1 (RC) 2
2 2
R R 2 消去，整理得： Z ' Z ' ' 2 2
圆心为 (R/2，0), 半径为R/2的圆的方程
阻抗是一个复数，可表示为实部 ZRe和虚部 ZIm两部分，

电化学阻抗谱简介(EIS).

Results and Discussion
• I-V curves of TiO2/CuInS2 devices at different temperatures in the dark
Good diode behavior at all temperatures.

IS of TiO2/CuInS2 devices at different potentials and temperatures
EIS测量结果的表达形式
• Y = G()X G()为阻抗或者导纳，总称阻纳。它是一个随频率变化的矢量，用变量为f或其角频率为的复变函数表示，可记为： G() ＝ G’() ＋jG’’() 若G为阻抗，则有Z() ＝ Z’() ＋jZ’’() 相位角＝arctg(-Z’’/Z’)
n-n-p system
TCO
n-TiO2 140 nm
p-CuInS2 130 nm
Carbon spot
(graphite conductive adhesive, 2.3 mm)
Spray pyrolysis
40 nm n-CuInS2
Techniques for the measurement of homojunction in CIS
Equivalent circuit
Schematic diagram of DSC
B.-K. Koo,et al, J Electroceram. 2006,17 ,79-82
Variation of efficiency of DSSC using Pt electrodes and CNT electrode with time
B.-K. Koo,et al, J Electroceram. 2006,17 ,79-82

电化学阻抗谱简介 (EIS) ppt课件

phase angle presentation
Charge-transfer at the platinum counter electrode
High (kHz)
Photoinjected electrons within the TiO2
Nernstian diffusion within the electrolyte
Middle(10~100 Hz ) Low (mHz)
• 以小幅值的正弦波对称的围绕稳定电位极化，不会引起严重的瞬间浓度变化及表面变化。
• 由于通过交变电流是在同一电极上交替地出现阳极过程和阴极过程，即使测量信号长时间作用于电解池，也不会导致极化现象的积累性发展。（准稳态方法）
• 速度较快的子过程的阻抗谱出现在比较高的频率域，而速度较慢的子过程的阻抗谱则出现在比较低的频率域，可据此判断子过程的数目及其动力学特征。
• 稳定性条件
– 电极系统在受到扰动后时，其内部结构所发生的变化不大，可以在受到小幅度扰动之后又回到原先的状态。
曹楚南pp、t课张件鉴清著，《电化学阻抗谱导论》，52002年
如何测量得到EIS?
• 装置简图
Lock-in amplifier (EG&G, M5210).
Potentiostat (EG&G, M273)
为扰动信号的电化学测量方法。
角频率为正弦波信号X
电流或者电位
电极系统
角频率为正弦波信号Y
电位或者电流
Y = G()X
G()为阻抗或者导纳
在一系列下测得的一组这种频响函数值就是电极系统的EIS，即G()～
曹楚南pp、t课张件鉴清著，《电化学阻抗谱导论》，32002年

电化学阻抗谱分析

6.1 有关复数和电工学知识－复数
1 复数的概念
（1）复数的模
Z Z'2Z''2
（2）复数的辐角（即相位角）
arctg Z ''
Z'
6.1 有关复数和电工学知识－复数
（3）虚数单位乘方
j 1 j2 1 j3 j
（4）共轭复数
ZZ'jZ'' Z Z ' jZ ''
6.1 有关复数和电工学知识－复数
一般说来，如果系统有电极电势E和另外n个表面状态变量，那么就有n+1个时间常数，如果时间常数相差5倍以上，在Nyquist图上就能分辨出n+1个容抗弧。第1个容抗弧（高频端）是(RpCd)的频响曲线。
补充内容
常见的规律总结
有n个电极反应同时进行时，如果又有影响电极反应的x个表面状态变量，此时时间常数的个数比较复杂。一般地说，时间常数的个数小于电极反应个数n和表面状态变量x之和，这种现象叫做混合电势下EIS的退化。
RL
1 *C d
* 1 R LC d
6.4 溶液电阻可忽略时电化学极化的EIS
Y=YR p＋ YC d＝ R 1pj C d1jR p C dR p
Z1(R RppCd)2j1 (RR p2C pC dd)2
Z'
1
Rp
(RpCd
)2
Z''
1
Rp2Cd (RpCd
)2
6.4 溶液电阻可忽略时电化学极化的EIS
（2）乘除
( a j b ) ( c j d ) ( a c b d ) j ( b c a d ) (a jb ) (cjd ) a c c 2 d b d 2j(b c c 2 d a d 2)

电化学阻抗谱中ohms和ohm cm2转换

电化学阻抗谱中ohms和ohm cm2转换1. 介绍电化学阻抗谱电化学阻抗谱（Electrochemical Impedance Spectroscopy，EIS）是一种用于研究电化学反应动力学和界面特性的分析技术。

通过测量电化学系统对交流电信号的阻抗响应，可以揭示电化学界面的特性，包括电化学反应速率、电化学界面的电荷转移和质传过程等信息。

2. EIS中的阻抗单位：ohms和ohm cm2在电化学阻抗谱中，阻抗通常以ohms（Ω）为单位。

而在某些情况下，我们也会遇到以ohm cm2（Ω cm2）为单位的阻抗。

两者之间的转换关系是非常重要的，因为在不同的研究领域和实验中可能会涉及到不同的阻抗单位。

3. Ohms和ohm cm2的转换关系在电化学阻抗谱中，阻抗的单位通常是以ohms（Ω）表示的。

当需要将ohms转换为ohm cm2时，需要考虑到电化学系统的几何形状和实际电极尺寸。

在电化学研究中，通常会用到标准电极表面积来表示电化学反应发生的实际表面大小，标准电极表面积的单位通常是cm2。

要将ohms转换为ohm cm2，可以使用以下公式：R (ohm cm2) = R (ohm s) × A其中，R代表阻抗，A代表标准电极表面积。

通过这个公式，可以将ohms转换为ohm cm2，以更准确地表示电化学系统的阻抗特性。

4. 实际案例分析举例来说，如果一个电化学系统的阻抗为1000 ohms，而标准电极表面积为0.1 cm2，那么将其转换为ohm cm2的计算如下：R (ohm cm2) = 1000 ohms × 0.1 cm2 = 100 ohm cm2通过这个简单的例子，可以清楚地看到ohms和ohm cm2之间的转换关系，以及在实际应用中的重要性。

5. 结语在电化学研究中，对于阻抗谱中的ohms和ohm cm2的转换，需要考虑到电化学系统的结构和实际表面积，并使用适当的转换公式进行计算。

bisquert关于电化学阻抗谱EIS的经典书

CHAPTER 12IMPEDANCE SPECTROSCOPY: A GENERAL INTRODUCTION AND APPLICATION TODYE-SENSITIZED SOLAR CELLSJuan Bisquert and Francisco Fabregat-Santiago12.1 INTRODU C TIONImpedance Spectroscopy (IS) has become a major tool for investigating the properties and quality of dye-sensitized solar cell (DSC) devices. This chapter provides an intro-duction of IS interpretation methods focusing on the analysis of DSC impedance data. It also presents a scope of the main results obtained so far. IS gives access to funda-mental mechanisms of operation of solar cells, for which reason we discuss our views of basic photovoltaic principles required to realize the interpretation of the experi-mental results. The chapter summarizes some 10 years of experience of the authors with regard to modeling, measurement and interpretation of IS applied in DSC.A good way to start this subject is a brief recollection of how it evolved over the ﬁ rst years. The original “standard” conﬁ guration of a DSC [12.1] that emerged in the early 1990s is formed by a large internal area constituted of a nanostructured TiO 2 semiconductor, connected to a transparent conducting oxide (TCO) and coated with photoactive dye molecules. It is furthermore in contact with a redox I I −3−/ electrolyte that is in turn connected to a Pt-catalyzed counterelectrode (CE). The DSC was ini-tially developed to be a photoelectrochemical solar cell. Electrochemical Impedance Spectroscopy (EIS) is a traditional method, central to electrochemical science and technology. Electrochemistry usually investigates interfacial charge transfer between a solid conductor (the working electrode, WE) and an electrolyte. This is done with a voltage applied between the WE and CE, with the assistance of a reference electrode (RE), rendering it possible to identify the voltage drop at the interface between the WE and the electrolyte. In addition, the electrolyte often contains a salt that provides a large conductivity in the liquid phase and removes limitations by drift transport in an electrical ﬁ eld. Electrochemistry is thus mostly concerned with interfacial charge transfer events, possibly governed by diffusion of reactants or products. It is with EIS2 Dye-sensitizedcellssolarpossible to readily separate the interfacial capacitance and charge-transfer resistance, as well as to identify diffusion components in the electrolyte. A good introduction to such applications is given by Gabrielli [12.2].In solid state solar cell science and technology, the most commonly applied frequency technique is Admittance Spectroscopy (AS). By tradition, AS denominates a special method that operates at reverse voltage and evaluates the energy levels of majority carrier traps (in general, all those that cross the Fermi level) as well as trap densities of states [12.3]. In work on DSCs and other solar cells, we may be interested to probe a wide variety of conditions. Consequently, we generally use the denomina-tion Impedance Spectroscopy (IS) when referring to the technique applied in this context (rather than EIS or AS).Before the advent of DSC, IS had been largely applied in photoelectrochem-istry [12.4, 12.5]. This is a ﬁ eld widely explored since the 1970s, using compact monocrystalline or polycrystalline semiconductor electrodes for sunlight energy con-version [12.6-12.8]. In these systems, IS provides information on the electronic car-rier concentration at the surface, via Mott-Schottky plots (i.e., the reciprocal square capacitance versus the bias voltage) as well as on the rates of interfacial charge trans-fer [12.9-12.11]. Several important concepts, later to be applied in DSC, where estab-lished at that time, such as the bandedge shift by charging of the Helmholtz layer and the crucial role of surface states in electron or hole transfer to acceptors in solution [12.9, 12.10, 12.12-12.14]. Nonetheless, it was clearly recognized that applying IS in these systems is far from trivial, for example due to the presence of frequency disper-sion that complicates the determination of parameters [12.15]It was natural to apply such well-established electrochemical methods to DSC and several groups have done so [12.16-12.19]. However, in the early studies, it was necessary to clarify a conceptual framework of interpretation which took several years. On the one hand, the early diffusion-recombination model [12.20] was generally adopted for steady-state techniques and produced very good results when extended to light-modulated frequency techniques [12.21]. In this approach, the only role of the applied voltage is to establish the concentration of electrons at the edge of the TiO2 in contact with TCO [12.20, 12.21]. On the other hand, classical photoelectrochemical methods heavily rest on the notion of charge collection at the surface space-charge layer, while diffusion is viewed as an auxiliary component, at best [12.22]. Thus, in photoelectrochemistry of compact semiconductor electrodes, the main method to describe the system behavior is an understanding of the electric potential distribution between the bulk semiconductor and the semiconductor/electrolyte interface [12.7].Owing to these conﬂ icting approaches, in the DSC area there were many discus-sions concerning the distribution of the applied voltage as internal “potential drops”, the origin of photovoltage, screening, and the role of electron-hole separation at the space-charge region [12.23-12.27]. This is understandable since the DSC is a porous, heterogeneous system, and in models of systems with a complex morphology, it is generally difﬁ cult to match diffusion control with a precise statement regarding the electrical potential distribution. The key element for progress is to adopt a macro-homogeneous approach and focus in the spatial distribution of the Fermi level. This method emerged in the DSC area [12.24, 12.28-12.30] and eventually led to gener-alized photovoltaic principles based on the splitting of Fermi levels and the c rucialspectroscopy 3 Impedancerole of selective contacts [12.31-12.34]. Another central concept that appeared in the DSC area was a “conduction band capacitance” [12.26, 12.28, 12.30], later to be generally deﬁ ned as a chemical capacitance [12.35]. This capacitive element is nor-mally absent in classical photoelectrochemistry but is key for the interpretation of frequency-resolved techniques in DSC. Also important was the recognition [12.26, 12.36] that nanostructured TiO2 should be treated as a disordered material, much like the amorphous semiconductors [12.37-12.39], with electronic traps affecting not only the surface events, but any differential/kinetic measurements, including the chemical capacitance [12.35], recombination lifetime and transport coefﬁ cients [12.40].The passage from established ideas of photoelectrochemistry to those best suited to the DSC have inevitably rendered it necessary to treat the porous-mixed phase structure of the DSC. Electrochemistry was already evolving in this direction for some decades, ﬁ rst with the description of porous electrodes [12.41], and then, with the introduction of truly active electrodes that become modiﬁ ed under bias voltage, such as intercalation metal-oxides [12.42], conducting polymers [12.43] and redox polymers [12.44]. Especially important is the work of Chidsey and Murray [12.44], which shows the modiﬁ cation of the diffusion coefﬁ cient in the solid phase, as well as the capacitance of the solid material as a whole, in opposition to the standard interfa-cial capacitance. In the analysis of these systems, either porous or not, the importance of coupling transport elements with interfacial and/or recombination components for a proper description of IS data was well recognized. Transmission line models pro-vide a natural representation of the IS models and are widely used [12.43, 12.45].As demonstrated in Figure 12.1, transmission line models incorporating fre-quency dispersion, which is ubiquitous in disordered materials, have been developed and applied to nanostructured TiO2 used in DSC. A very good realization of the model was soon found in the experiment, as shown in Figure 12.2 [12.46]. Later, diffusion-reaction models were solved for IS characterization, and the models where put in rela-tion to both nanostructured semiconductors and bulk semiconductors for solar cells [12.47]. Disorder was included also in generalized transmission lines for anomalous diffusion [12.48]. In addition, the role of macroscopic contacts was analyzed in gen-eralized transmission line models, as shown in Figure 12.1(b) [12.49], and this effect would take relevance as a result of the TCO contribution to the measured impedance [12.50, 12.51].The calculation of the diffusion-recombination impedance [12.47] opened the way for a direct measurement of conductivity of electrons in TiO2 by IS [12.52], which provided a good validation of the method. Further, the diffusion- r ecombination impedance also naturally reveals [12.47] the chemical capacitance of electrons in nanostructured TiO2 (associated to the rise of the Fermi level), which also appears in measurements of cyclic voltammetry (at slow scan rates) [12.53] and electron lifetime [12.54].Application of these IS methods and models to DSC [12.51] demonstrated that IS provides a picture of the energetics of TiO2, which is a crucial tool for compar-ing DSC conﬁ gurations [12.55]. It also showed that it was possible to simultane-ously obtain the parameters for transport and recombination at various steady-state conditions of a DSC, which is an unsurpassed power of the technique. The trends of the electron diffusion coefﬁ cient [12.51] where similar to those found previouslyImpedance spectroscopy 7and we can also write Eq. (12.1) in terms of V ocjj q v v mk Tqv mk T =−−−−sc oc B oc B 11e e ()// (12.3)Bias voltage is denoted “forward” when it injects charge in the solar cell and induces recombination. Otherwise it is referred to as “reverse”. By changing the illumination intensity Φ0, one can trace curves similar to that in Figure 12.3(a) with other values of j sc and V oc . The values and shape of these curves for a given solar cell allow us to determine the energy conversion efﬁ ciency of the photovoltaic device, Figure 12.3(b). Another crucial parameter is the ﬁ ll factor (FF), which is the maxi-mum electrical power delivered by the cell with respect to j V sc oc ⋅, Figure 12.3(b). A high FF requires that the current remains high at the maximum power point. This is obtained if the j-V curve is reasonably “squared” as in Figure 12.3(a).12.2.2 Physical origin of the diode equation for a solar cellIt is important to clarify the physical interpretation of the diode equation. We consider a slab of p-type semiconductor with thickness L . At a position x , n is the density of minority carriers (electrons), and j n the ﬂ ux in the positive x direction. The conserva-tion equation can be written as:∂∂=+−−n t x G x G x Jx x U x ()()()()()Φ∂∂d nn (12.4)where G Φ is the rate of optical photogeneration (per unit volume) due to the illumi-nation intensity Φ0 (photons·cm −2), while G d is the rate of generation in the dark by the surrounding blackbody radiation. U n is the rate of recombination of electrons per volume. A simple and important model is the linear form, with electron lifetime t 0U nn =t 0(12.5)Eq. (12.4) must hold locally, in equilibrium, therefore, assuming Eq. (12.5), we haveG n d =0t (12.6)where n 0 is the carrier density in dark equilibrium. This is due to, the rate of genera-tion in dark equilibrium, by detailed balance principle, equilibrating the recombina-tion rate [12.31]. A similar constraint on G d applies for any recombination model.The ﬂ ux of electron carriers with the diffusion coefﬁ cient D 0 relates to the gra-dient of concentration by Fick’s lawJ D nx n =−∂∂0 (12.7)Impedance spectroscopy 9If we restrict our attention to a steady-state condition, Eq. (12.11) reduces to: j qLG qL U G =−−Φ[]n d (12.12)Comparing Eqs. (12.1) and (12.12), the photocurrent generated during short-circuit becomes:j qLG sc =Φ (12.13)The total generation per unit area, LGΦ is proportional to the incident lightintensity, LG ΦΦ=h opt 0, where h opt is an optical quantum yield that depends on the properties of absorption of the radiation by the solar cell. We also obtain that: j qLG d d = (12.14)Consequently, the dark reverse current corresponds to the extraction of the car-riers generated by the thermal surrounding radiation.We already appreciate that the ideal diode model of a solar cell states that a constant current is drawn out of the cell, namely j sc + j d , which corresponds to all the electron carriers generated in the semiconductor. In addition, the recombination term produces a current in the opposite direction. At high forward bias the recombination term dominates and bends the j-V curve, as indicated in Figure 12.3(a). Note that this ideal model does not contain any trace of diffusion whatsoever. The only element required in order to obtain the diode model is to state that the contacts are selective, and extract only one carrier at each side, as indicated in Figure 12.4.Another step for converting the conservation equation into a j -V characteristic is to relate the carrier density, n , to the applied voltage, V , by introducing Fermi levels. We assume the extended states for electrons at the level E c (conduction band edge), with an effective density, N c . With respect to the electron Fermi level E Fn , we have:n N e E E k T =−c Fn c B ()/ (12.15)and considering the dark (equilibrium) Fermi level E F0,n N e EE k T 0=−c F0c B ()/ (12.16)we obtainn n e E E k T =−00()/Fn F B (12.17)The voltage, V , is measured at the selective contacts, and corresponds to the dif-ference in Fermi levels of carriers at the contacts. If the contacts are ideally reversible[12.33], each contact separately equilibrates with the Fermi level of electrons, E Fn , and holes, E Fp . This gives:V E E q =−()/Fn Fp (12.18)For a p-semiconductor, the holes in the Fermi level remain at the dark equilib-rium level, E E Fp F0=, and Eq. (12.18) can thus be written:E E qV Fn F0=+ (12.19)f = v /2p , typically over several decades, i.e., from mHz to 10 MHz, with 5-10 meas-urements per decade. At each frequency the impedance meter must verify that the Z (v ) is stable. At low frequencies, this takes a considerable amount of time, i.e., stabilizing a measurement at f = 10 mHz consumes minutes. Nevertheless, measurements at low frequencies are often important in order to make sure that one is approaching the dc regime, as further explained below. A judicious selection of the frequency window of measurement is therefore necessary, and this is often aided by experience.In addition to scanning the frequencies, it is usually very important to deter-mine the IS parameters at various conditions of steady state. This is the key approach in order to relate the measurement to a given physical model. At each steady state the Z (v ) data is related to a model in the frequency domain, which is usually represented as an equivalent circuit. By modifying the steady state, the change in impedance parameters (resistances, capacitances, etc.) can be monitored in relation to the physi-cal properties of the system. Since the impedance measurement takes a considerable amount of time, the steady state often changes along the impedance measurement, and precautions should be taken to avoid a serious drift of the parameters. In par-ticular, care should be taken with unintentional changes of temperature in solar cells, since this introduces additional and unwanted variations of the parameters.Note that, at each steady state, a full scan of frequencies is necessary. Thus many steady state points imply a long measurement, perhaps over an entire day. However, data that do not cover different steady states may in some cases be of little value, particularly if there is uncertainty regarding the meaning of the parameters. It is also important to verify the true signiﬁ cance of parameters by material varia-tions of the samples, e.g., to conﬁ rm the correlation of a transport resistance with the reciprocal length of the sample. The extent to which these approaches must be judiciously realized depends on the preliminary knowledge and experience of the particular system.12.3.1 Steady state and small perturbation quantitiesAs an example of the relationship between the ac impedance and steady-state quan-tities, we discuss a characteristic experiment on a solar cell using the ideal model outlined in Figures 12.3 and 12.4. We choose a certain point of bias voltage, V 0, with the associated current density, j 0. At this point, a small displacement of voltage ˆ()V 0 implies a change of current ˆ()j 0. The value v= 0 in parenthesis indicates that thedisplacement is inﬁ nitely slow, i.e., ˆ()V 0 and ˆ()j 0 attain a value that is independent oftime. The displacement of the current and voltage is indicated in Figure 12.3(a) with arrows.For a solar cell with area A , the quotient of the small quantities gives:Z V Aj AdjdV R 0001()=()()=⎛⎝⎜⎞⎠⎟=−ˆˆdc (12.23)In other words, the small quantities provide a derivative of the voltage with respect to the current. This is the reciprocal of the slope of the j -V curve, which is in turn the dc resistance of the solar cell R dc (per area) under those particular conditions.voltage acting on them is identical. Using Kirchhoff rules, we add the impedances for two elements in series and the resulting impedance is an equivalent description of the initial connection (under an applied voltage, it produces the same current as the combination that it replaces). For elements in parallel, we add the admittances (or the complex capacitances) to form the equivalent impedance.A ﬁ rst example of an equivalent circuit is the R 1C 1 series combination. From the impedanceZ R i C ()v v =+111(12.31)we obtain the complex capacitanceC C i *()v v =+111t (12.32)Table 12.6 Impedance representations.Denomination Deﬁ nition* Real and imaginary parts Impedance Z (v ) Z = Z ′ + iZ ″Admittance Y Z ()()v v =1Y = Y ′ + iY ″Phase angle tan d =Z Z ″′Complex capacitance C i Z *()()v v v =1C * = C ′ + iC ″Conductivity s *()()v v =LAZ s * = s ′ + i s ′, s ′(0) ≡ sComplex dielectric constant e *(v ) = LC*(v )/A e * = e ′ + i e ″s * = i ve *Complex electric modulus M *()()v v =1e M * = M ′ + iM ″*L is the length of the sample, A is the area.Table 12.7 Basic ac electrical elements.Denomination Symbol Scheme Impedance Resistance R R Capacitance C 1i Cv Inductor L i v L Constant phase element (CPE) Q n ()i Q nnv −Here, the relaxation time is deﬁ ned ast = R 1C 1 (12.33)Let us look more closely at the meaning of the relaxation time, t 1, in relation to the response of the system in the time domain. We consider the type of measurement commented before, in which a change of voltage, ΔV , is applied at time t = 0, and for which the subsequent evolution of the electrical current is monitored. In the frequency domain, the step voltage ˆ()()V t V u t =⋅Δ has the expression:ˆ()V s Vs =Δ (12.34)and the electrical current can be written:ˆ()ˆ()()()()I s V s Z s V sZ s VR s ===+ΔΔt t 1111 (12.35)By inverting Eq. (12.35) to the time domain, we obtain:I t V R e t ()/=−Δt 1(10.36)In general, the process described by Eqs. (12.32) or (12.36) is an elementary relaxation with the characteristic frequency:v 111111==t R C (12.37)The plot of the complex capacitance is shown in Figure 12.8(a). The capaci-tance displays an arc from the dc value C *(0) = C 1 to the high frequency value. The top of the arc occurs at the characteristic frequency of the relaxation v 1. The impedance, shown in the complex plane in Figure 12.8(b), forms a vertical line. This is a “blocking” circuit, since the impedance of a capacitor is ∞ at low frequency, which effectively constitutes an open circuit connection, thus preventing the dc cur-rent from ﬂ owing. However, the impedance of the capacitor decreases as the fre-quency increases, and at very large frequencies, with respect to v 1, the capacitor indeed becomes a short-circuit. Consequently, there remains only the resistance R 1. The impedance of a resistor is the same at all frequencies, hence the vertical line in Figure 12.8(b). The arc in Figure 12.8(a) is a manifestation of an elementary relaxa-tion process that corresponds to an exponential decay in the time domain, indicated in Eq. (12.36).Another important example of an equivalent circuit is the RC parallel combina-tion, depicted in Figure 12.9. The admittance of the combination is here:Y R i C 1111()v v =+ (12.38)respect to the frequency, Figure 12.10(c), usually reveals a great deal of information. In Figure 12.10(c), we observe two plateaus of the real part of the capacitance which clearly indicate two distinct relaxation processes. These relaxations are manifested in the peaks of the loss component of the capacitance, C ′. When increasing the frequency, each peak of C ′ indicates the occurrence of a relaxation and a consequent decrease of the capacitance [12.72]. Such features can also be observed in the complex capacitance plot in Figure 12.10(a), demonstrating separate arcs for the two relaxations.Let us consider in more detail how to obtain the parameters of a given IS data set. The main method consists in ﬁ tting by least squares methods using an equivalent circuit software that is available in many kinds of measuring equipments. However, the ﬁ tting process requires the assumption of a given equivalent circuit, and sometimes, in addition, the input of reasonable trial parameters. As we have mentioned before, the inspection of the data set in several complementary representations usually provides a good hint of the equivalent circuit structure, at least in the less complex cases. Another useful approach is to read the parameter values directly from the data representation, e.g., resistances and capacitances of separate contributions. How to perform this has already been discussed in the examples of Figures 12.9(b) and 12.10(c). However, the values of capacitance or impedance in a certain frequency domain can be inﬂ uenced by the whole equivalent circuit. So, to obtain the circuit parameters, there is often no substitute for integral data ﬁ tting. Separately treating part of the spectral data is a valuable resource, but one that should be used with care.For instance, in Figure 12.9(a) we observe that the impedance displays a verti-cal line when approaching the dc limit. Therefore, at low frequency, Figure 12.9(a) can be simply described by RC parallel combination. The low frequency resistance is clearly given by R dc . But what should be used as the low frequency capacitance C lf ? It cannot be C 1, otherwise the arc would ﬁ nish at the origin of Figure 12.9(a), which it does not. In general, it is very useful to obtain the impedance formula in a restricted frequency domain, and the method is demonstrated with this example.First, from the expression of the impedance in Eq. (12.39), we ﬁ nd the low frequency limit, which gives:Z R R i R C ()v v =++12121 (12.40)This last equation does not correspond to any recognizable combination of cir-cuit elements. In fact, we seek a parallel combination, which should provide a good description of the data in Figure 12.9(a) at low frequencies. Consequently, we trans-form Eq. (12.40) to the admittance, maintaining the ﬁ rst order approximation in v , with the result:Y R R i R R R C ()()v v =+++112121221 (12.41)In Eq. (12.41), we readily recognize the parallel RC admittance formula. The low frequency capacitance is:C R R R C lf =+121221() (12.42)The capacitance therefore depends on the resistances of the original circuit. This result is quite natural, since the capacitance relates to the reciprocal of the impedance (see Table 12.6), and the latter is greatly inﬂ uenced by the series resistance. However, the result in Eq. (12.42) cannot be inferred without a proper calculation.Let us continue with the analysis of the effect of different types of equiva-lent circuit elements. While the combination of resistances and capacitors provides a spectrum that remains in the ﬁ rst quadrant of the complex impedance plane, it is not uncommon to ﬁ nd that the data cross to the fourth quadrant. One reason for this is the inductance of the leads, which very frequently causes a tail at high frequencies in which the spectrum crosses the real axis. A different feature is often found in several types of solar cells at low frequency , consisting in a loop that forms an arc in the fourth quadrant [12.76]. One of the representations of this effect is a series RL branch com-plementing the RC circuit of Figure 12.9. The model is shown in Figure 12.11, and the total admittance has the valueY R R i L i C ()v v v =+−+111331 (12.43)The low frequency limit of Eq. (12.43) is writtenY R i C L R ()v v =+−⎛⎝⎜⎞⎠⎟101332 (12.44)Eq. (12.44) shows that, when R 3 is small, the capacitance becomes negative at low frequencies, i.e., C = −C N with the valueC LR C N =−3321 (12.45)The spectra with both a positive and negative low frequency capacitance are shown in Figure 12.11(a). If R 3 < (L 3/C 1)1/2, the impedance traces a low frequency arc in the fourth quadrant, otherwise, the impedance remains in the ﬁ rst quadrant. The intercept of Z with the real axis (i.e., the transition of C ′(v ) to negative values) occurs at the frequencyv NC=−⎛⎝⎜⎞⎠⎟⎡⎣⎢⎢⎤⎦⎥⎥11132312L C R L / (12.46)In the capacitance vs. frequency representation, Figure 12.11(b), the presence of the inductor appears as the negative contribution that becomes more negative towards lower frequencies. At high frequencies, the plot is dominated by C 1, whereas at lower frequencies, the circuit capacitance starts to decrease due to the inductive effect. At v NC , it shows a dip at the transition from positive to negative values, after which the absolute value increases towards lower frequencies, until it saturates at the value − C N .As a ﬁ nal example of the simple equivalent circuits, we consider the presence of a Constant Phase Element (CPE) as shown in Figure 12.12. The normal application ofcircuits render it possible to visualize the structure of the model and to separately treat data portions in certain relevant frequency windows. However, equivalent circuits are by no means necessary in order to establish a physical model; what is needed is an impedance function, in any of all its possible analytical representations.It should also be mentioned, that not all complex functions of frequency are valid impedance responses. The complex function Z(v) must obey causality condi-tions (i.e., the stimulus must precede the response), which imposes analytical con-straints known as Kramers-Kronig transforms [12.72]. These transforms enable the construction of the real part of Z(v) provided that the imaginary part is known at all frequencies, and vice versa. Using equivalent circuit elements, such as those of Table 12.6, ensures that the resulting model obeys the Kramers-Kronig relations. 12.4 B ASIC PHYSICAL MODEL AND PARAMETERS OF IS INSOLAR CELLS12.4.1 Simplest impedance model of a solar cellIn the process of obtaining physical information from IS data, it is necessary to relate the observable equivalent circuit elements with the system properties. As mentioned before, equivalent circuits are a useful tool for interpretation, and the signiﬁ cance attached to the circuit elements, the potential in the circuit, etc., may be quite different from the standard physics textbook examples.This is particularly the case in the analysis of solar cells. Note that the ac-equivalent circuits that we have discussed are composed of passive elements (i.e., resistances and capacitances). It is common to interpret the ﬂ ow of charges in cir-cuits in terms of the mechanistic view of the drift of charges in an electrical ﬁ eld caused by potential differences. This image is also very popular for explaining the photovoltaic action, e.g., in a p-n junction, in terms of an electric ﬁ eld that sends oppositely charged carriers in different directions. However, a solar cell is a kind of battery, i.e., an element producing an electromotive force, and such an element cannot work with electrostatic voltage differences alone. According to Volta’s idea, the electromotive force is an nonelectrostatic action on charges in conductors that causes unequal charges to separate and remain separated [12.78]. We thus wish to obtain the internal ac-equivalent circuit of a solar cell using only linear elements associated to a small signal ac perturbation, with emphasis on the interpretation of the elements that make it work as a device for the production of electricity. The key approach for useful reading of ac-equivalent circuits of DSC, is that potentials in the circuit represent an electrochemical potential of electrons (or holes) in the actual device.To clarify this, we start with the simplest model of a solar cell, discussed above in Sec. 12.2.2, which contains the necessary elements without complications of car-rier transport, speciﬁ c features of selective contacts, etc. We calculate the IS response of the solar cell of Figure 12.4 [12.35], corresponding to the application of a small ac electrical perturbation.。

电化学阻抗谱

C0k – Ck ＝ k, k = 1, 2, …, m，于是根据泰勒展开定理可将Gi 围绕C0k , k = 1, 2, …, m 展开,我们假定各初始值C0k与其真值非常接近，亦即，k非常小 (k = 1, 2, …, m)，因此可以忽略式中 k 的高次项而将Gi近似地表达为： G G X ( C 1 0 ,,C 0 2,C 0 m )+ 1 m C G k• C k
电化学阻抗谱方法是一种以小振幅的正弦波电位（或电流）为扰动信号的电化学测量方法。由于以小振幅的电信号对体系扰动，一方面可避免对体系产生大的影响，另一方面也使得扰动与体系的响应之间近似呈线性关系，这就使测量结果的数学处理变得简单。
同时，电化学阻抗谱方法又是一种频率域的测量方法，它以测量得到的频率范围很宽的阻抗谱来研究电极系统，因而能比其他常规的电化学方法得到更多的动力学信息及电极界面结构的信息。
线性条件。当一个状态变量的变化足够小，才能将电极过程速度的变化与该状态变量的关系作线性近似处理。
稳定性条件。对电极系统的扰动停止后，电极系统能回复到原先的状态，往往与电极系统的内部结构亦即电极过程的动力学特征有关。
因果性条件
当用一个正弦波的电位信号对电极系统进行扰动，因果性条件要求电极系统只对该电位信号进行响应。这就要求控制电极过程的电极电位以及其它状态变量都必须随扰动信号——正弦波的电位波动而变化。控制电极过程的状态变量则往往不止一个，有些状态变量对环境中其他因素的变化又比较敏感，要满足因果性条件必须在阻抗测量中十分注意对环境因素的控制。
电化学阻抗谱的数据处理与解析
1. 数据处理的目的与途径 2. 阻纳数据的非线性最小二乘法拟合原理 3. 从阻纳数据求等效电路的数据处理方法

电化学阻抗谱简介 (EIS)

C−2-V plots of a TCO/TiO2 /CuInS2/carbon device at different temperatures.
Junction Models
T<340 K
340K<T<400 K
p-n-n system
FDRFDR FDR Full Depletion Region (FDR)
曹楚南、张鉴清著，《电化学阻抗谱导论》，2002年
哪些体系适合进行EIS测定?
• 因果性条件
– 当用一个正弦波的电位信号对电极系统进行扰动，要求电极系统只对该电位信号进行响应。
• 线性条件
– 只有当一个状态变量的变化足够小，才能将电极过程速度的变化与该状态变量的关系近似作线性处理。
• 稳定性条件
f = 100Hz ~ 1MHz
For frequencies above 100 kHz, the R1C1 branch dominates over the others. Accordingly, at 1 MHz C1, being the space-charge capacitance, can be calculated directly from the imaginary part of the impedance Z”.
B.-K. Koo,et al, J Electroceram. 2006,17 ,79-82
Application in the measurement of conductivity
CNT Pt
No significant change
Initial : 17 ohm After 5 days: 62.5 ohm

eis电化学阻抗谱测试方案

eis电化学阻抗谱测试方案电化学阻抗谱（EIS）是一种常见的电化学测试方法，用于研究电化学系统的界面和电荷传递行为。

本文将提供一份完整的方案，介绍EIS测试的原理、仪器设置、样品制备和数据分析等方面，以指导EIS测试的进行。

一、原理介绍EIS测试通过在待测系统中施加一个小振幅的交流电信号，并测量系统的响应，从而得到系统的阻抗谱。

阻抗谱通常由两个坐标轴组成：实部（Z'）和虚部（Z''）。

实部代表系统的电阻部分，虚部代表系统的电容和电感部分。

通过分析阻抗谱的形状和特征频率，可以获得有关系统界面的信息，如电解质电导率、电荷传输过程及界面阻抗等。

二、仪器设置1.电化学工作站：包括电源和数字锁相放大器等。

选择适合实验要求的电源和放大器，保证实验信号的稳定性。

2.电解池：选择适当的电解池，如玻璃池或电化学池，容量要适应样品的尺寸。

3.参考电极：通常选择银/氯化银电极作为参考电极，确保电解质的稳定性。

4.工作电极：根据实验要求选择合适的工作电极，如玻碳电极、金电极等。

5.配套的电极支撑和电解池盖：确保电解池中的电极能够牢固固定，并且有良好的密封性能。

三、样品制备1.清洗和抛光工作电极：将工作电极从电化学池中取出，使用硅砂纸和研磨液进行清洗和抛光，然后用去离子水彻底清洗干净。

2.准备电解质：根据实际需要制备适当浓度的电解质，如盐酸溶液、硝酸溶液等。

使用去离子水稀释后，用电导仪测量电解质的电导率，确保浓度准确。

3.将工作电极插入电解质中，并使用电极支撑进行固定。

确保电极与电解质充分接触，避免气泡和电极脱落。

四、测试步骤1.连接仪器：将电源和数字锁相放大器与电化学工作站连接，确保信号传输畅通。

2.设置实验参数：根据样品的特点和实验要求，设置交流信号的振幅、频率范围和扫描速率等实验参数。

3.执行实验：打开电化学工作站，将工作电极插入电解质中，开始进行阻抗谱测试。

测试时要保持电解池内的电解质充分搅拌，以确保电解质的均匀性。

电化学阻抗谱分析方法

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Electrochemical Impedance Spectroscopy
A resistance and capacitance in parallel (Randles circuit)
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Electrochemical Impedance Spectroscopy
I E F 0

Resistance:
Z R
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Z
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F -90

Review of ac circuits
• Components along the ordinate are assigned as imaginary and along the abscissa are real, thus, we handle these parameters mathematically as “real” or “imaginary”.
Use „find circle“ option Use linear regression to evaluate a Warburg impedance
•Take care of:
Non uniqueness of equivalent circuit models Weighting the data
30 5 15 1

ElectrochemicalImpedance Spectroscopy 电化学阻抗谱分析方法

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Electrochemical Impedance Spectroscopy
A resistance and capacitance in parallel (Randles circuit)
Z=Rs at high frequency Z=Rct+Rs at low frequency
Use „find circle“ option Use linear regression to evaluate a Warburg impedance
•Take care of:
Non uniqueness of equivalent circuit models Weighting the data
• Where Xc is the capacitive reactance, 1/ωC • A comparison of R and Xc shows that Xc must carry dimensions of resistance, but the magnitude of Xc falls with increasing frequency.
Electrochemical Impedance Spectroscopy
A Resistance and capacitance in series In electrochemical cell: R=Rs: solution resistance C=Cd: double layer capacitance

电化学阻抗测量技术与阻抗谱的数据处理

Байду номын сангаас
电化学阻抗谱的数据处理与解析
1. 数据处理的目的与途径 2. 阻纳数据的非线性最小二乘法拟合原理 3. 从阻纳数据求等效电路的数据处理方法 (Equivcrt) 4. 依据已知等效电路模型的数据处理方法 (Impcoat) 5. 依据数学模型的数据处理方法 (Impd)
数据处理的目的
1.根据测量得到的EIS谱图, 确定EIS的等效电路或数学模型，与其他的电化学方法相结合，推测电极系统中包含的动力学过程及其机理； 2.如果已经建立了一个合理的数学模型或等效电路，那么就要确定数学模型中有关参数或等效电路中有关元件的参数值，从而估算有关过程的动力学参数或有关体系的物理参数
• 对于复杂的电路，首先将整个电路分解成２个或２个以上互相串联或互相并联的“盒”，每个盒必须具有可以作为输入和输出端的两个端点。这些盒可以是等效元件、简单的复合元件（即由等效元件简单串联或并联组成的复合元件）、或是既有串联又有并联的复杂电路。对于后者，可以称之为复杂的复合元件。如果是简单的复合元件，就按规则（１）或（２）表示。于是把每个盒，不论其为等效元件、简单的复合元件还是复杂的复合元件，都看作是一个元件，按各盒之间是串联或是并联，用规则（１）或（２）表示。然后用同样的方法来分解复杂的复合元件，逐步分解下去，直至将复杂的复合元件的组成都表示出来为止。
现在用C1，C2，…，Cm表示这m个参量的估计值，将它们代入到式 (8.2.1) 中，就可以计算出相应于 Xi的Gi 的数值。gi - Gi 表示测量值与计算值之间的差值。在Ｃ 1,Ｃ 2 ，…，Ｃ m 为最佳估计值时，测量值与估计值之差的平方和S的数值应该最小。Ｓ就称为目标函数：Ｓ =Σ (gi - Gi )2 由统计分析的原理可知，这样求得的估计值C1， C2，…，Cm为无偏估计值。求各参量最佳估计值的过程就是拟合过程

电化学阻抗谱的原理

电化学阻抗谱的原理电化学阻抗谱(Electrochemical Impedance Spectroscopy, EIS)是一种表征电化学系统的技术手段，通过对电化学系统进行交流电信号的激励并测量响应，进而分析电化学过程中的电荷转移和质传过程。

在EIS中，电化学系统被视为由电阻(R)、电感(L)和电容(C)等元件组成的等效电路。

通过在电化学系统上施加固定幅值、不同频率的正弦交流电信号，测量电流和电势之间的相位差和幅值关系，以获得电化学系统的阻抗谱。

阻抗谱通常以复数形式表示，包括实部和虚部两个分量。

实部表示电阻性损耗，虚部表示电容性或电感性反应。

EIS的原理可以通过以下几个关键步骤来解释：1.正弦波激励：在电化学系统中施加正弦交流电信号，以激发电化学过程中的电荷转移和质传过程。

2.频率扫描：在一定的频率范围内对电化学系统进行频率扫描，即逐渐改变激励信号的频率。

3.电势响应测量：测量电化学系统中电势与时间的变化，通常使用电势计或参考电极来实现。

4.电流响应测量：测量交流电信号激励下的电化学系统中的电流变化，通常使用锁相放大器或示波器等设备来实现。

5.数据处理：通过对测量得到的电势和电流响应进行处理，计算得到电化学系统的阻抗谱。

常见的数据处理方法包括频域分析和等效电路拟合等。

EIS的原理基于交流电信号在电化学系统中的传播和响应。

在电化学过程中，电荷转移和质传过程在交流电信号的激励下会导致系统的阻抗发生变化。

因此，通过测量激励信号和响应信号之间的幅值和相位差，可以获得电化学系统内部的电荷转移和质传过程的信息。

这些信息对于研究电极反应动力学和界面化学过程等具有重要的意义。

EIS在材料科学、电化学储能、腐蚀研究等领域具有广泛应用。

它可以用于表征电极材料的电化学性能、分析电化学反应机理、评估电化学界面的质量和储能设备的性能等。

其原理和应用使得EIS成为一种非常有用和强大的研究工具。

电化学阻抗谱分析方法【英文】

Mixed kinetic and diffusion control Cdl or CPE RW
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Left: Voltammetric curves of 1 mmol/L ferrocene on the
GC eletrode with different rotation rate, rotation rate
Electrochemical Impedance Spectroscopy
A resistance and capacitance in parallel (Randles circuit)

电化学阻抗谱欧瑞姆 pdf

电化学阻抗谱欧瑞姆 pdf
电化学阻抗谱（Electrochemical Impedance Spectroscopy，EIS）是一种用于研究电化学系统的技术和方法。

它通过在电化学系统中施加交流电信号，并测量系统的响应来获得关于系统电化学特性的信息。

EIS广泛应用于电化学领域，如电池、腐蚀、电解、电化学传感器等。

欧姆定律是电学的基本定律之一，它描述了电流、电压和电阻之间的关系。

根据欧姆定律，电流等于电压除以电阻。

在电化学阻抗谱中，欧姆电阻是指电化学系统中的纯电阻成分，它表示了电流通过电解质溶液或电极界面时的阻力。

电化学阻抗谱通常以图形的形式呈现，其中横轴表示频率或角频率，纵轴表示阻抗大小。

通过分析电化学阻抗谱图形的特征，可以得到有关电化学系统的信息，如电解质溶液的电导率、电极界面的电荷转移过程、电极表面的反应速率等。

关于"欧瑞姆pdf"的具体含义不太清楚，可能是指与欧姆定律相关的PDF文档。

在互联网上可以找到很多关于电化学阻抗谱和欧姆定律的PDF文档，这些文档可以提供更深入的理论知识、实验方
法和应用案例等方面的信息。

总结起来，电化学阻抗谱是一种研究电化学系统的技术，通过测量系统的响应来获取有关电化学特性的信息。

欧姆定律是电学的基本定律之一，描述了电流、电压和电阻之间的关系。

关于电化学阻抗谱和欧姆定律的PDF文档可以提供更深入的理论和实验方面的信息。

电化学阻抗法计算极片迂曲度

电化学阻抗法计算极片迂曲度电化学阻抗法（Electrochemical Impedance Spectroscopy, EIS）是一种强大的技术，用于分析和理解电化学系统中的界面现象和电荷传输过程。

在锂离子电池的极片（电极）分析中，EIS可以用来评估电极材料的电导率、电荷转移电阻以及锂离子的扩散行为。

迂曲度（tortuosity）是一个描述多孔材料中孔隙结构的参数，它反映了孔隙路径的弯曲程度。

在电化学阻抗谱中，迂曲度可以通过分析Warburg阻抗（Zw）来间接计算。

Warburg阻抗与电极材料的扩散性质有关，而扩散性质又与孔隙结构密切相关。

计算极片迂曲度的步骤通常包括：1. EIS测试：首先对极片进行EIS测试，以获取不同频率下的阻抗谱。

2. 数据分析：分析EIS谱中的Warburg阻抗（Zw）随频率（f）的变化。

Warburg阻抗通常在高频区域接近一个恒定的值，这个值可以用来估计扩散电阻（Rd）。

3. 计算扩散系数：使用Warburg方程（Zw = σ * (ω^0.5) * (C^0.5) * (Rd)）来计算锂离子的扩散系数（DLi+），其中σ是电解质的电导率，C是电解质的浓度，Rd是扩散电阻。

4. 估计迂曲度：通过比较实验测得的扩散系数（DLi+）与理论值（Dth）来估计迂曲度。

理论值Dth可以根据电极材料的孔隙率和活性物质的扩散系数来计算。

5. 孔隙率计算：如果需要，可以通过其他方法（如BET 分析）来测量电极材料的孔隙率。

6. Bruggeman关系式：使用Bruggeman关系式来估算迂曲度，该式通常用于描述多孔材料的电导率与孔隙率之间的关系。

需要注意的是，通过EIS计算迂曲度是一个相对复杂的过程，需要专业的电化学阻抗谱分析软件和适当的实验数据。

此外，EIS提供的是关于整个电极系统的信息，而不是单个颗粒或孔隙的信息，因此计算得到的迂曲度是一个宏观的参数，它反映了电极整体的结构特性。

电化学阻抗谱方法（EIS）

以测量得到的频率范围很宽的阻抗谱来研究电极系统，速度快的子过程出现在高频区,速度慢的子过程出现在低频区,可判断出含几个子过程，讨论动力学特征。
Seminar I
EIS测量的前提条件
因果性条件: 测定的响应信号是由输入的扰动信号引起的；线性条件: 对体系的扰动与体系的响应成线性关系；稳定性条件: 电极体系在测量过程中是稳定的,当扰动停止后，体系将回复到原先的状态；有限性条件：在整个频率范围内所测定的阻抗或导纳值是有限的.
曹楚南，张鉴清,电化学阻抗谱导论,科学出版社，2002
Seminar I
复合元件的CDC示例
按规则(1)将这一等效电路表示为: R CE-1 按规则(２),CE-1可以表示为 (Q CE-2). 因此整个电路可进一步表示为： R(Q CE-2) 将复合元件CE-2表示成: (Q(W CE-3)) 整个等效电路就表示成： R(Q(W CE-3)) 将简单的复合元件CE-3表示出来。应表示为(RC),于是电路可以用如下的
高频端的近似: 低频端的近似:
Z = R + s
Z= 1
Q2+鉴清,电化学阻抗谱,讲义，2005
Seminar I
含锌Ni(OH)2碱性电池的EIS谱图
0%的DOD(放电深度)时不同Zn含量的Zn-Ni(OH)2碱性充电电池的EIS谱图 H.Chen,JQ Zhang, J Solid State Electrochem,2005 9:421-428
Seminar I
Ni电极的等效电路图
等效电路图
物理意义： Rs:从参比电极到工作电极的溶液电阻 CPE:与双电层电容关联的常相位角元件 Rt:电极的电荷转移电阻 Wo:固相扩散的沃伯格阻抗

电化学阻抗谱

电化学阻抗谱电化学阻抗谱（ElectrochemicalImpedanceSpectroscopy， EIS）是一种用于研究电化学特性的非常有效的技术。

它使用微弱电流或电压信号来测量物体的电阻和电容，从而了解物体结构和材料性质。

电化学阻抗谱可以用来监测和调整复杂的物理系统，包括腐蚀控制，电池技术和氧化物层厚度等。

本文综述了电化学阻抗谱的基本原理和应用，以及它的创新技术和新进展。

什么是电化学阻抗谱电化学阻抗谱是一种用于研究电化学特性的技术，它可以用来监测和调整复杂的电化学系统，如腐蚀和电池技术等。

EIS使用微弱电流或电压信号来测量物体的电阻和电容，从而获得物体结构和材料性质的信息。

它显示出电路中各元件间及其相互作用的电性参数。

EIS运行的基本原理是将电化学反应表示为一系列电路，其中包括源极电阻，电容，介质电阻（吸附、氧化还原作用和电解质反应）和电偶电阻。

在EIS测量中，对电场源施加一个小的正弦波，测量电路产生的反应，从而推断出电路中各元件间及其相互作用的电性参数。

EIS几乎可以用于任何电化学反应，但它在电池技术，腐蚀控制和氧化物层厚度等领域得到了特别广泛的应用。

它可以用于分析电池技术，电池性能和衰减，以及电池温度、电解质和电池组成的影响。

此外，它也可以用于研究金属的腐蚀，检测和控制金属的腐蚀，并确定它的腐蚀速率。

EIS也可以用于测量涂镀物的厚度，氧化物的层厚度，以及氧化物的形成等。

EIS的创新技术EIS的最新技术和进展使用了非常复杂的算法，新型测量技术和传感器，可以对微小电流信号进行快速准确的检测，从而更好地了解电池技术，腐蚀控制和氧化物层厚度等。

其中一项创新技术是分子束外延（MBE）技术。

MBE技术可以将氧化物层厚度测量精确到纳米尺度，该技术使用三维彩色图像，可以更精确地测量氧化物的厚度和电阻。

另一项创新技术是电化学生物传感器技术，它可以用来检测病毒、细菌和其他有害物质，并可以用于快速检测和监测环境污染。

电化学阻抗谱分析方法【英文】

电化学阻抗谱

电化学阻抗谱简介(EIS).

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电化学阻抗谱的原理

电化学阻抗谱分析方法【英文】

电化学阻抗谱 欧瑞姆 pdf

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电化学阻抗谱方法（EIS）

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电化学阻抗谱欧瑞姆 pdf