Copper solid electrolytes

Due to the high ionic conductivity of silver and copper solid electrolytes, several silver and copper microbatteries have been fabricated early, and it was found that they are impractical, with a low energy density and high cost. Thin films of silver compounds as the microbattery electrolyte were reviewed by Keimedy. ... 

In general, the properties of electrochemical capacitors are quite different from those of other types of capacitors. Like batteries, electrochemical capacitors are essentially low-voltage devices their breakdown occurs by electrolysis of the electrolyte. For aqueous electrolytes, the thermodynamic potential at which this occurs is about 1.2 volts. For organic solvent-based systems, it may be as high as 3 or 4 volts, whereas, for silver and copper solid electrolytes, it is less than 1 volt. This property severely limits the amount of stored energy (U) for a given capacitance because U = 1/2CV. ... 

As indicated in Table 31.4, the potential of ICPs is in somewhat esoteric applications. In some instances the potential has reached commercial realisation. For example, coating the walls of boreholes in circuit boards before electroplating with copper involves fewer stages than with older established processes and is claimed to be cost effective, faster and simpler. ICPs are also now being marketed in Japan for use in solid electrolyte conductors. 

H.-H. Hildenbrand, and H.-G. Lintz, Solid electrolyte potentiometry aided study of the influence of promotors on the phase transitions in copper-oxide catalysts under working conditions, Catalysis Today 9, 153-160 (1991). 

For any type of nonaqueous electrolyte (nonaqueous solutions, melts, solid electrolytes) we can select suitable reference electrodes, measure the potentials of other electrodes, and set up tables of electrode potentials. The order of the reactions (electrodes) as a rule does not strongly differ between the different media. A strong reducing agent such as lithium will have a more negative potential than a weaker reducing agent such as copper, both in water and in other media. 

Cul) is not due to point defects but to partial occupation of crystallographic sites. The defective structure is sometimes called structural disorder to distinguish it from point defects. There are a large number of vacant sites for the cations to move into. Thus, ionic conductivity is enabled without use of aliovalent dopants. A common feature of both compounds is that they are composed of extremely polarizable ions. This means that the electron cloud surrounding the ions is easily distorted. This makes the passage of a cation past an anion easier. Due to their high ionic conductivity, silver and copper ion conductors can be used as solid electrolytes in solid-state batteries. 

While the amount of electricity that can be conducted by polymer films and wires is limited, on a weight basis the conductivity is comparable with that of copper. These polymeric conductors are lighter, some are more flexible, and they can be laid down in wires that approach being one-atom thick. They are being used as cathodes and solid electrolytes in batteries, and potential uses include in fuel cells, smart windows, nonlinear optical materials, LEDs, conductive coatings, sensors, electronic displays, and in electromagnetic shielding. 

Figure 17.32 Photoaction spectra obtained in presence of Cu(I)/Cu(II) electron mediators using regenerative sandwich cells equipped with gold counter electrodes. (5) Stars, (1) open circles, (4) open triangles, (2) solid triangles, (3) open squares, and (6) solid circles. Data compared with the F/I3 couple (black squares). Li+ 0.5 M was added to all copper-based electrolytes.

Propene to acrolein. Hildenbrand and Lintz87,88 have used solid electrolyte potentiometry to study the effect of the phase composition of a copper oxide catalyst on the selectivity and yield of acrolein during the partial oxidation of propene in the temperature range of 420-510°C. Potentiometric techniques were used to determine the catalyst oxygen activity, and hence the stable copper phase, under working conditions. Hildenbrand and Lintz used kinetic measurements to confirm that the thermodynamically stable phase had been formed (it is known that propene is totally oxidised over CuO but partially oxidised over ). 

Since the discovery of the MAg4I5 compounds, very many more solid electrolytes have been reported. Sodium, lithium, copper, proton, oxide and fluoride solid electrolytes are now well known. An important example is sodium /3-alumina which was discussed in Chapter 8. The conductance... 

Lead and mercury are deposited as micron-sized clusters, predominantly at intercrystallite boundaries [105] so does lithium from the polyethylene oxide solid electrolyte. What is more, Li intercalates into the sp2-carbon [22, 138], Thus, observations on the Li intercalation and deintercalation enable one to detect non-diamond carbon on the diamond film surface. Copper is difficult to plate on diamond [139], There is indirect evidence that Cu electrodeposition, whose early stages proceed as underpotential deposition, also involves the intercrystallite boundaries [140], We note that diamond electrodes seem to be an appropriate tool for use in the well-known electroanalytical method of detection of traces of metal ions in solutions by their cathodic accumulation followed by anodic stripping. The same holds for anodic deposition, e.g. of, Pb as PbCh with subsequent cathodic reduction [141, 142], Figure 30 shows the voltammograms of anodic dissolution of Cd and Pb cathodically predeposited from their salt mixtures on diamond and glassy carbon electrodes. We see that the dissolution peaks are clearly resolved. The detection limit for Zn, Cd, and Pb is as low as a few ppb [143]. 

Copper cation conductors - solid electrolyte Copper-conducting solid electrolyte - solid electrolyte... 

Electrolytes are used in electrochemistry to ensure the current passage in -> electrochemical cells. In many cases the electrolyte itself is -> electroactive, e.g., in copper refining, the copper(II) sulfate solution provides the ionic conductivity and the copper(II) ions are reduced at the - cathode simultaneous to a copper dissolution at the - anode. In other cases of -> electrosynthesis or - electroanalysis, or in case of - sensors, electrolytes have to be added or interfaces between the electrodes, as, e.g., in case of the -> Lambda probe, a high-temperature solid electrolyte. 

Tubandt was a pioneer of - solid state electrochemistry. He introduced a methodology to determine the - transport numbers of ions in -> solid electrolytes [i], which is now referred to as -> Tubandt method. Together with his co-workers he performed seminal studies of conductivities and transport numbers of solid electrolytes, e.g., of silver, lead, and copper halides, and silver sulfide. He showed for the first time that the entire dark current of silver bromide is transported by silver ions, and also that slightly below the melting point silver iodide has a higher conductivity than the melt. 

Firstly, the figure of merit for an electrolyte is the conductance rather than the conductivity. Very useful polymer electrolytes have been developed for which the conductivity is 10" S cm" which is derisory in comparison with values of room temperature ionic conductivity that approach 1 Scm" both for typical dilute aqueous or non-aqueous electrolyte solutions and for optimized silver or copper-based solid electrolytes such as Rb4Cui6l7-x CI13-X [112, 113]. This is because polymer electrolytes are mechanically adequate to maintain a high-integrity barrier when sandwiched between anode and cathode, even when the electrolyte thickness is only 10-100 pm, corresponding to an electrolyte resistance of 1-10 Q. 

The first solid electrolytes with high copper ion conductivity at room temperature were discovered in 1973. An example is 7CuBrC6Hi2N4CH3Br, whose conductivity at room temperature is 0.017 cm Several other copper ion conductors have since been described. One of these conductors represented by the formula Rb4Cui6l7Cli3 has a conductivity of 0.34 cm at 25°C. This is the solid... 

Another interesting application of perovskite-based hydrogen sensors, which has now been commercialized, is for monitoring hydrogen in molten metal such as aluminium, zinc and copper (Yajima and Iwahara 1992). As cerates were not entirely suitable, the investigators used CaZr03 doped with indium oxide as the solid electrolyte (Iwahara 1996). 

These few examples of the application of solid state galvanic cells in the field of solid state reactions can only present a very limited view of this important area of solid state science. The examples were chosen primarily in order to demonstrate the principles according to which solid state research in thermodynamics and kinetics should be conducted with the use of electrochemical tools and methods. Such measurements are only possible because of the existence of suitable solid electrolytes. The most important of these are Zr02(-f CaO) and Th02(+Y2 03) for oxygen, silver halides and Ag4Rbl5 for silver, copper halides for copper, some glasses in which certain ions are dissolved, and p — Al2 03(-hNaO) for sodium. 

Goonetilleke, P.C., Babu, S.V., Roy, D., 2005. Voltage-induced material removal for electrochemical mechanical planarization of copper in electrolytes containing N03, glycine, and H2O2. Electrochem. Solid State Lett. 8, G190—G193. 

The purpose of this tutorial paper is to review the theory, the method of measurement and treatment of the data for experiments on polarized solid electrolytes according to the theory of C. Wagner and the developments of H. Rickert, K. Weiss, D. 0. Raleigh, A. Joshi and others. Methods to obtain the total and electronic conductivities, transport number, number and mobility of electronic charge carriers and the double layer capacitance at the electrolyte-electrode interface are to be discussed. Examples will be chosen which exhibit good agreement with theory— primarily the silver and copper halides. 

VARIOUS UTILISATIONS OF SOLID ELECTROLYTES tent of the molten copper before casting. 

To protect the solid electrolyte when it is inserted through the slag layer into the molten steel, a thin copper or steel cap covers it. This cap dissolves rapidly in the steel and measurement is performed after about 15 seconds when thermal equilibrium is reached. Probes have very limited life at their temperature of utilisation which is around l600 C and have to be discarded after each measurement. ... 

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