Electrochemical quartz crystal

An electrochemical quartz crystal microbalance (EQCM or QCM) can be used to estimate the surface roughness of deposited lithium [43],... 

The electrochemical quartz crystal microbalance (EQCM) is a powerful tool for elucidating interfacial reactions based on the simultaneous measurement of electrochemical parameters and mass changes at electrode surfaces. The microbalance is based on a quartz crystal wafer, which is sandwiched between two electrodes, used to induce an electric field (Figure 2-20). The field produces a mechanical oscillation... 

Such approximation is valid when the thickness of the polymeric layer is small compared to die thickness of die crystal, and the measured frequency change is small with respect to the resonant frequency of the unloaded crystal. Mass changes up to 0.05% of die crystal mass commonly meet this approximation. In die absence of molecular specificity, EQCM cannot be used for molecular-level characterization of surfaces. Electrochemical quartz crystal microbalance devices also hold promise for the task of affinity-based chemical sensing, as they allow simultaneous measurements of both tile mass and die current. The principles and capabilities of EQCM have been reviewed (67,68). The combination of EQCM widi scanning electrochemical microscopy has also been reported recently for studying die dissolution and etching of various thin films (69). The recent development of a multichannel quartz crystal microbalance (70), based on arrays of resonators, should further enhance die scope and power of EQCM. 

EC mechanism, 34, 42, 113 E. Coli, 186 Edge effect, 129 Edge orientation, 114 Electrical communication, 178 Electrical double layer, 18, 19 Electrical wiring, 178 Electrocapillary, 22 Electrocatalysis, 121 Electrochemical quartz crystal, microbalance, 52 Electrochemihuiiinescence, 44 Electrodes, 1, 107... 

Wei C, Myung N, Rajeshwar K (1994) A combined voltammetry and electrochemical quartz crystal microgravimetry study of the reduction of aqueous Se(lV) at gold. J Electroanal Chem 375 109-115... 

Saloniemi H, Kemell M, Ritala M, Leskela M (2000) PbTe electrodeposition studied by combined electrochemical quartz crystal microbalance and cyclic voltammetry. J Electroanal Chem 482 139-148... 

In the case of Ni(OH)2 and conductive polymer electrodes, solvent and anions intercalate into the electrode at anodic potentials. Electrochemical quartz crystal microbalance (EQCM) is a useful technique for monitoring the ingress and egress of solvent and anions in these materials. 

The electrochemical quartz crystal microbalance (EQCM) is a very useful technique for detecting small mass changes at the electrode surface that accompany electrochemical processes. In 1880, Jacques and Pierre Curie discovered that when stress was applied to some crystals, such as quartz, it resulted in an electrical potential across the... 

Electrochemical Quartz Crystal Microbalance Fntnre advances will require the coupling of EQCM with spectroscopic techniqnes that yield chemical information. EQCM has been conpled with ellipsometry (Gottesfeld et al., 1995). However, ellip-sometry does not yield chemical information. 

Hepel, M., Electrode-solntion interface studied with electrochemical quartz crystal nanobalance, in Interfacial Electrochemistry, A. J. Wieckowski, Ed., Marcel Dekker, New York, 1999, p. 599. 

Ward, M. D., Principles and applications of the electrochemical quartz crystal microbalance, in Physical Electrochemistry, I. Rubenstein, Ed., Marcel Dekker, New York, 1995, p. 293. 

Leopold et al. and Nyholm et al. have investigated this oscillatory system by in situ confocal Raman spectroscopy [43], and in situ electrochemical quartz crystal microbalance [44], and in situ pH measurement [45] with the focus being on darification of the osdllation mechanism. Based on the experimental results, a mechanism for the oscillations was proposed, in which variations in local pH close to the electrode surface play an essential role. Cu is deposited at the lower potentials ofthe oscillation followed by a simultaneous increase in pH close to the surface due to the protonation... 

Bohannan, E. W., Huang, L. Y Miller, F. S., Shumsky, M. G. and Switzer, J. A. (1999) In situ electrochemical quartz crystal microbalance study of potential oscillations during the electrodeposition of CU/CU2O layered nanostructures. Langmuir, 15, 813—818. 

Jerkiewicz G, Vatankhah G, Lessard J, Soriaga MP, Park YS. 2004. Surface-oxide growth at platinum electrodes in aqueous H2SO4 Reexamination of its mecharusm through combined cyclic-voltammetry, electrochemical quartz-crystal nanobalance, and Auger electron spectroscopy measurements. Electrochim Acta 49 1451-1459. 

Studies have shown that the Pt oxides are not hydrated [Birss et al., 1993 Harrington, 1997 Jerkiewicz et al., 2004]. Electrochemical quartz crystal microbalance [Birss et al., 1993] and nanobalance [Jerkiewicz et al., 2004] experiments... 

We have found new CO-tolerant catalysts by alloying Pt with a second, nonprecious, metal (Pt-Fe, Pt-Co, Pt-Ni, etc.) [Fujino, 1996 Watanabe et al., 1999 Igarashi et al., 2001]. In this section, we demonstrate the properties of these new alloy catalysts together with Pt-Ru alloy, based on voltammetric measurements, electrochemical quartz crystal microbalance (EQCM), electrochemical scanning tunneling microscopy (EC-STM), in situ Fourier transform infrared (FTIR) spectroscopy, and X-ray photoelectron spectroscopy (XPS). 

Uchida H, Ikeda N, Watanahe M. 1997. Electrochemical quartz crystal microhalance study of copper ad-atoms on gold electrodes. Part II. Further discussion on the specific adsorption of anions from the solutions. J Electroanal Chem 424 5-12. 

Uchida H, Ozuka H, Watanahe M. 2002. Electrochemical quartz crystal microhalance analysis of CO-tolerance at Pt-Fe alloy electrodes. Electrochim Acta 47 3629-3636. 

Electric field effects in DFT, 76-77, 98-100, 145-146 Electrochemical Quartz Crystal... 

Gao, G., Y. Wurm et al. (1997). Electrochemical quartz crystal microbalance, voltammetry, spectroelectrochemical, and microscopic studies of adsorption behavior for (7E,7 Z)-diphenyl-7,7 -diapocarotene electrochemical oxidation product. J. Phys. Chem. B 101 2038-2045. 

The Electrochemical Quartz Crystal Microbalance d 2.2.7—FTIR and Related Techniques... 

The first application of the quartz crystal microbalance in electrochemistry came with the work of Bruckenstein and Shay (1985) who proved that the Sauerbrey equation could still be applied to a quartz wafer one side of which was covered with electrolyte. Although they were able to establish that an electrolyte layer several hundred angstroms thick moved essentially with the quartz surface, they also showed that the thickness of this layer remained constant with potential so any change in frequency could be attributed to surface film formation. The authors showed that it was possible to take simultaneous measurements of the in situ frequency change accompanying electrolysis at a working electrode (comprising one of the electrical contacts to the crystal) as a function of the applied potential or current. They coined the acronym EQCM (electrochemical quartz crystal microbalance) for the technique. 

Kemell, M. Saloniemi, H. Ritala, M. Leskela, M. 2001. Electrochemical quartz crystal microbalance study of the electrodeposition mechanisms of CuInSe2 thin films. /. Electrochem. Soc. 148 010-018. 

An application of an electrochemical quartz crystal microbalance (EQCM) in the study of the A11/HCIO4 system shows that even at a potential about 0.5 V more negative than the onset of AuO formation (the so-called preoxide region), the resonant frequency of the Au-covered quartz crystal decreases as that of the surface mass increases. A comparison of a voltammogram with the potential dependence of the micro-balance frequency for an Au electrode is shown in Figs. 6a and 6b. 

The electrochemical quartz crystal microbalance (EQCM) method was first used to study underpotential deposition in 1988 for Pb, Bi, Cu,... 

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