Ref reference electrode

Figure 13. Representation of the potential variations in the electrochemical cell and associated electronic schemes (a-d). ( = cat + Ri + an see text). W, working electrode Ref, reference electrode A, auxiliary electrode, (e) Schematic description of the electrochemical cell with a potentiostat.

Figure 5.21. Schematic representation of a thin-layer electrochemical cell (A) and a wall-jet electrochemical cell (B). AUX = auxiliary electrode, REF = reference electrode and WE = working electrode.

WE working electrode Ref reference electrode CE counter-electrode The dotted arrow symbolizes the existing link between the voltage indicated by the voltmeter (controlled voltage between WE and Ref) and the actual voltage delivered by the power supply between WE and CE. 

Figure 15.14 Schematic of a simple potentiostat and representation of the cell as an electrical (equivalent) circuit. WE, working eleotrode REF, reference electrode CE, counterelectrode.

Ref reference electrode C counter electrode W working electrode... 

Fig. 2 Schematic structure of bending actuators, (a) bilayer and (b) trilayer actuators operating in liquid electrolyte, (c) trilayer and (d) pseudo-trilayer actuators containing their own electrolyte and operating in open-air. fVB working electrode, CE counter-electrode. Ref reference electrode. ECP electronic conducting polymer, PVDF Polyvinylidenefluoride. IPN interpenetrating polymer network...

Fig. 6.4 Combination of an RF heating unit (framed arrangement, right) with a common potentiostat (/ ) to form a hot-wire electrochemical device. The triggering facility is necessary only for pulse heating. Potentiostat inputs REF reference electrode, WORK working electrode, AUX auxiliary (counter) electrode...

Fig. V-17. Schematic diagram for the apparatus for measurement of Vobs (see text). The vibrating reference electrode is positioned close to the surface of a AgN03 solution in which there is an Ag electrode, which, in turn, is in electrical contact with the reference electrode. (From Ref. 196.)...

Fig. 17-9 Example of the arrangement of anodes and reference electrodes from Ref. 13.

Checking the absence of internal mass transfer limitations is a more difficult task. A procedure that can be applied in the case of catalyst electrode films is the measurement of the open circuit potential of the catalyst relative to a reference electrode under fixed gas phase atmosphere (e.g. oxygen in helium) and for different thickness of the catalyst film. Changing of the catalyst potential above a certain thickness of the catalyst film implies the onset of the appearance of internal mass transfer limitations. Such checking procedures applied in previous electrochemical promotion studies allow one to safely assume that porous catalyst films (porosity above 20-30%) with thickness not exceeding 10pm are not expected to exhibit internal mass transfer limitations. The absence of internal mass transfer limitations can also be checked by application of the Weisz-Prater criterion (see, for example ref. 33), provided that one has reliable values for the diffusion coefficient within the catalyst film. 

FIG. 7 Simplified equivalent circuit for charge-transfer processes at externally biased ITIES. The parallel arrangement of double layer capacitance (Cdi), impedance of base electrolyte transfer (Zj,) and electron-transfer impedance (Zf) is coupled in series with the uncompensated resistance (R ) between the reference electrodes. (Reprinted from Ref. 74 with permission from Elsevier Science.)... 

FIG. 19 Dependence of the half-wave potentials for Fc (curve 1) and ZnPor (curve 2) oxidation in benzene on CIO7 concentration in the aqueous phase. In these measurements, half-wave potentials were extracted from reversible steady-state voltammograms obtained at a 25 pm diameter Pt UME. The benzene phase contained 0.25 M tetra-w-hexylammonium perchlorate (THAP) and either 5 mM Fc or 1 mM ZnPor. All potentials were measured with respect to an Ag/AgCl reference electrode in the aqueous phase. (Reprinted from Ref. 48. Copyright 1996 American Chemical Society.)... 

FIG. 1 Electrical potential oscillation across the nitrobenzene membrane and schematically illustrated features of the diffusion of yellowish substances in the U-shaped cell (a) potentiometer, (b) aqueous phase, (c) nitrobenzene phase, (d) KCl salt bridge, and (e) Ag/AgCl reference electrode. (Ref 4.)... 

FIG. 2 Electrical potential oscillation across the nitrobenzene membrane (A) and between nitrobenzene and aqueous phases on the left (B) and right (C) (a-d) Ag/AgCl reference electrodes, (e-h) KCl salt bridges. (Ref. 4.)... 

Figure 26. EXAFS spectroelectrochemical cell (A) front view, (B) top view, (C) side view, (D) assembly (a) auxiliary electrode compartment, (b) working electrode well, (c) reference electrode compartment, (d) X-ray window, (e) inlet port, (f) auxiliary electrode lead, (g) RVC working electrode, (h) Pt syringe needle inlet and electrical contact, (i) Pt wire auxiliary electrode, (j) Ag/AgCl(3M NaCl) reference electrode. (From Ref. 98, with permission.)...

Fig. 3. Diagrams of electrochemical cells used in flow systems for thin film deposition by EC-ALE. A) First small thin layer flow cell (modeled after electrochemical liquid chromatography detectors). A gasket defined the area where the deposition was performed, and solutions were pumped in and out though the top plate. Reproduced by permission from ref. [ 110]. B) H-cell design where the samples were suspended in the solutions, and solutions were filled and drained from below. Reproduced by permission from ref. [111]. C) Larger thin layer flow cell. This is very similar to that shown in 3A, except that the deposition area is larger and laminar flow is easier to develop because of the solution inlet and outlet designs. In addition, the opposite wall of the cell is a piece of ITO, used as the auxiliary electrode. It is transparent so the deposit can be monitored visually, and it provides an excellent current distribution. The reference electrode is incorporated right in the cell, as well. Adapted from ref. [113],...

Figure 2. Flow cell (excluding pump and titration cell). Left Front view. Right Cross section along center line. I. Perspex cover. 2. Outlet tube (back to titration cell). 3. Flow channel. 4. Counter electrode (platinum). 5. Metal plate with cut edge exposed in the channel. 6. Seal of molded silicone rubber. 7. Piston for removal of air fix>m reference electrode compartment. 8. Reference electrode compartment. 9. Capillary holes connecting 8 to 3.10. Inlet tube (from titration cell). II. Reference electrode (Ag/AgCI, sat. KCI). (Reprinted from Ref. 3, with kind permission from Elsevier Science Ltd., Kidlington, Oxford, UK.)...

Figure 48. Anodic stability as measured on a spinel LL-Mn204 cathode surface for EMS-based electrolytes (a) Lilm (b) LiC104 (c) LiTf. In all cases, 1.0 m lithium salt solutions were used, and slow scan voltammetry was conducted at 0.1 mV s with lithium as counter and reference electrodes and spinel LiJV[n204 as working electrode. (Reproduced with permission from ref 75 (Figure 3). Copyright 1998 The Electrochemical Society.)...

Figure 8.11. Induction period for the solution 0.3 M EDTA, 0.05 M CUSO4, pH 12.50, 2.5 g/L paraformaldehye, Cu electrode, 2.2 cm, 25°C, SCE reference electrode, argon atmosphere. (From Ref. 31, with permission from the Electrochemical Society.)...

Potentials of some reference electrodes relative to either the standard hydrogen electrode or the saturated calomel electrode. Further data in ref. [17]. 

Fig. 7 Cyclic voltammetry of O2 in pyridine, at a stationary mercury drop electrode. Reference electrode aqueous SCE scan rate 45 mV s potential scale from —0.6 to —1.05 V (Reproduced with permission from Ref. 35).

Fig. 27 Electrocatalysis of NOx reduction in the presence of 2 10 M CU4P4W30 in a pH 5 medium. The scan rate was 2 mV s, the working electrode was glassy carbon and the reference electrode was SCE. (a) Nitrate (b) nitrite. For more detailed information, see text (taken from Ref 115).

Undoubtedly, the mercury/aqueous solution interface, was in the past, the most intensively studied interface, which was reflected in a large number of original and review papers devoted to its description, for example. Ref. 1, and in the more recent work by Trasatti and Lust [2] on the potentials of zero charge. It is noteworthy that in view of numerous measurements of the double-layer capacitance at mercury brought in contact with NaF and Na2S04 solutions, the classical theory of Grahame [3] stiU holds [2]. According to Trasatti [4], the most reliable PZC value for Hg/H20 interface in the absence of specific adsorption equals to —0.433 0.001 V versus saturated calomel electrode, (SCE) residual uncertainty arises mainly from the unknown liquid junction potential at the electrolyte solution/SCE reference electrode boundary. 

Pavlishchuk and Addison [11] have discussed the foregoing discrepancies and made careful measurements of the reference electrodes commonly utilized by investigators in measuring potentials in acetonitrile. The correction to be applied for converting a potential measured against a reference electrode, ref to the ferrocene standard. Eye, can be expressed as ... 

All aqueous potential values are referenced to the standard hydrogen electrode. Nonaqueous potential values are referenced to ferrocene (Fc) if possible. Other references are indicated in parentheses where SCE represents the standard calomel electrode, A1 represents the Ag/Ag+ reference electrode ([Ag+] = 0.01 M unless otherwise indicated) and A2 represents the Ag/AgCl reference electrode. In acetonitrile, potential values referenced to SCE may be corrected to the ferrocene reference standard by subtracting 0.380 V, depending upon the anion present (a) Ref 11, (b) Ref 10c. c [Ag+] = 0.1 M. 

Cu"/ ([9]aneS3)2 + +. Potentials shown are versus a Ag/AgCl reference electrode. The current scale differs slightly for each voltammogram but the peaks generally range from about —5 to +5 pA (data from Ref 68). 

Fig. 3.5,19 Open-circuit voltage (K. ) for CdS formed in 9-layer CdAr films as a function of particle size (estimated from UV/visible absorption spectra). The electrolyte was 1.0 M Na2S03 at pH 7.25, and platinum and standard calomel electrodes were used as the counter and reference electrodes, respectively. (From Ref. 5.)...

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