Capacitance spectroscopy

P. M. Mooney, Defect Identification Using Capacitance Spectroscopy... 

Watkins and Pfromm (1999) suggested a further method based on capacitance spectroscopy in the range 102 105 Hz to identify and tracking membrane fouling with organic macromolecules, such as sulfonated lignin, in real times. 

Watkins, E.J. and Pfromm, P.H. 1999. Capacitance spectroscopy to characterize organic fouling of electrodialysis membranes. J. Membr. Sci. 162, 213-218. 

A1 Al-doped ZnO thin him as ohmic back contact of ZnO hlms with Pd Schottky contact on top, improved frequency response enables capacitance spectroscopy DLTS [57,59]... 

The application of capacitance spectroscopy as for example DLTS (see Sect. 7.4.3 and 7.4.5) requires high-quality Schottky contacts to ZnO single... 

Scanning force spectroscopy (SFS) Force-distance curves Amplitude-distance curves Phase-distance curves Frequency-distance curves - Kelvin probe spectroscopy - Scanning capacitance spectroscopy Full-resonance spectroscopy (FRS) AFAM resonance spectroscopy (AFAM-RS) Scanning spreading resistance spectroscopy (SSRS)... 

Heath J, Zabierowski P (2011) Capacitance spectroscopy of thin-fibn solar cells. In Abou-Ras D, Kirchartz T, Rau U (eds) Advanced characterization techniques for thin film solar cells. Weinheim, Wiley-Vch, Chap 4, p 81... 

Scanning capacitance spectroscopy Full-resonance spectroscopy (FRS)... 

The capacitance. The electrical double layer may be regarded as a resistance and capacitance in parallel see Section 20.1), and measurements of the electrical impedance by the imposition of an alternating potential of known frequency can provide information on the nature of a surface. Electrochemical impedance spectroscopy is now well established as a powerful technique for investigating electrochemical and corrosion systems. 

The combination of photocurrent measurements with photoinduced microwave conductivity measurements yields, as we have seen [Eqs. (11), (12), and (13)], the interfacial rate constants for minority carrier reactions (kn sr) as well as the surface concentration of photoinduced minority carriers (Aps) (and a series of solid-state parameters of the electrode material). Since light intensity modulation spectroscopy measurements give information on kinetic constants of electrode processes, a combination of this technique with light intensity-modulated microwave measurements should lead to information on kinetic mechanisms, especially very fast ones, which would not be accessible with conventional electrochemical techniques owing to RC restraints. Also, more specific kinetic information may become accessible for example, a distinction between different recombination processes. Potential-modulation MC techniques may, in parallel with potential-modulation electrochemical impedance measurements, provide more detailed information relevant for the interpretation and measurement of interfacial capacitance (see later discus-... 

This does not imply that this double layer is at its point of zero charge (pzc). On the contrary, as with every other double layer in electrochemistry, there exists for every metal/solid electrolyte combination one and only one UWr value for which this metal/gas double layer is at its point of zero charge. These critical Uwr values can be determined by measuring the dependency onUWR of the double layer capacitance, Cd, of the effective double layer at the metal/gas interface via AC Impedance Spectroscopy as discussed in Chapter 5.7. 

In summary AC impedance spectroscopy provides concrete evidence for the formation of an effective electrochemical double layer over the entire gas-exposed electrode surface. The capacitance of this metal/gas double layer is of the order of 100-300 pF/cm2, comparable to that corresponding to the metal/solid electrolyte double layer. Furthermore it permits estimation of the three-phase-boundary length via Eq. 5.62 once the gas exposed electrode surface area NG is known. 

The interpretation of phenomenological electron-transfer kinetics in terms of fundamental models based on transition state theory [1,3-6,10] has been hindered by our primitive understanding of the interfacial structure and potential distribution across ITIES. The structure of ITIES was initially studied by electrochemical and thermodynamic analyses, and more recently by computer simulations and interfacial spectroscopy. Classical electrochemical analysis based on differential capacitance and surface tension measurements has been extensively discussed in the literature [11-18]. The picture that emerged from... 

The use of conventional electrochemical methods to study the effect of metal adatoms on the electrochemical oxidation of an organic adsorbate may be in some cases of limited value. Very often, in the potential region of interest the current due to the oxidation of an organic residue is masked by faradaic or capacitive responses of the cocatalyst itself. The use of on-line mass spectroscopy overcomes this problem by allowing the observation of the mass signal-potential response for the C02 produced during the oxidation of the adsorbed organic residue. 

Table 3. Capacitance values (F g1) of the KOH activated carbons (A-C A-CS A-PM A-PS A-AC) estimated by galvanostatic discharge, cyclic voltammetry and impedance spectroscopy. ecific ca acitancejiF m alculated erjurfdceareao carbon.

Sample Galvanostatic discharge C/Fg1 Cyclic voltammetry C/Fg1 Impedance spectroscopy C/Fg1 Specific capacitance uF cm 2... 

Figure 5 presents the capacitance-frequency dependence from impedance spectroscopy measurements for CS48 and CS15 in acidic and organic medium. In the low frequency region (from ImHz to lOOmHz) nearly a complete penetration of the ions into the pores is allowed and the quite stable values indicate the domination of the capacitive behavior at the electro 1 ytc/carbon interface. All the curves show a typical drop of... 

A. Poghossian, M.H. Abouzar, F. Amberger, D. Mayer, Y. Han, S. Ingebrandt, A. Offenhauser, and M.J. Schoning, Field-effect sensors with charged macromolecules characterisation by capacitance—voltage, constant capacitance, impedance spectroscopy and atomic-force microscopy methods. Biosens. Bioelectron. 22, 2100-2107 (2007). 

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