Electrolyte applications, high-temperature

Silvester, L. F. Pitzer, K. S. "Thermodynamics of Electrolytes. 8. High-Temperature Properties, Including Enthalpy and Heat Capacity with Application to Sodium Chloride" J. Phys. Chem., 1977, 81, 1822. 

One of the earliest applications of fast ion conductors was the use of stabilized zirconia as the oxide ion electrolyte in high-temperature fuel cells. Fuel cells are electrochemical devices that convert chemical energy of a fuel-burning reaction such as... 

L. F. Silvester and K. S. Pitzer, Thermodynamics of electrolytes. 8. High-temperature properties, including enthalpy and heat capacity, with application to sodium chloride , J. Phys. Chem., 81, 1822-1828 (1977). 

This book presents metals treatment and recovery technologies from nine different industries that are also applicable to similar metal-bearing streams from other industries. Established metal recovery and treatment technologies are detailed including chemical precipitation, electrolytic recovery, high-temperature recovery, membrane separation, leaching, adsorption, and evaporation. 

In a recent patent application, Angell et al. described a series of alkylammonimn PILs, which are potentially useful as nonaqueous electrolytes in high-temperature polymer membrane fuel cells. The PILs investigated were stable to temperatures between 200 and 250 C, had conductivities comparable to aqueous solutions, and could be enhanced through the addition of a base with a pA a value intermediate between that of the acid and the base. ... 

Typical Applications High temperature detergents, textiles, emulsifiers, high electrolyte solutions. Stabilizer. 

In the early years, extensive work was carried out to synthetically modify PBI derivatives using different chemical structures of the monomers, i.e., different tetraamine and dicarboxylic acid derivatives, as comprehensively reviewed by Neuse et al. [2]. Since the mPBI membrane was successfully demonstrated as the membrane electrolyte in high temperature PEM fuel cells, much effort has been devoted to the synthesis of various novel PBI derivatives in order to improve the physicochemical properties of the membranes and their durability in fuel cells [9, 10]. This section summarizes the recent synthetic efforts on PBI structure analogues, primarily for applications in the high temperature PEM fuel cells. Table 7.1 lists the chemical structures of PBI variants with modified main chains. 

Due to their remarkable ionic conductivity, LaNbo,84Wo,i604,o8 electrolytes found applications in electrolysis. They were successfully synthesized and also proposed as electrolyte for high-temperature fuel cells. The reason for the better performance in electrolysis mode was suggested to be associated with the inherent oxygen excess of the LaNbo.84Wo.i6O4 os phase [71]. 

Laguna-Bercero, M.A., Bayliss, R.D., and Skinner, S.J. (2014) LaNb0.84W0.i6O4.08 as a novel electrolyte for high temperature fuel cell and solid oxide electrolysis applications. Solid State Ionics, 262, 298-302. 

Ishiahara, T., Sammes, N.M. and Yamamoto, O. (2003), Electrolytes, in High Temperature Solid Oxide Fuel Cells Fundamentals, design and Applications, Eds. S.C. Singhal and K. Kendall, Elsevier, UK, pp. 83-117. 

Reviews of batch calorimeters for a variety of applications are published in the volume on Solution Calorimetry [8] cryogenic conditions by Zollweg [22], high temperature molten metals and alloys by Colinet andPasturel [19], enthalpies of reaction of inorganic substances by Cordfunke and Ouweltjes [16], electrolyte... 

The hardness of the film is markedly affected by the conditions of anodising. By means of special methods involving dilute electrolytes at low temperatures and relatively high voltages , with or without superimposed alternating current, it is possible to produce compact abrasion-resistant films with thicknesses of 50-75/im and hardnesses of 200-500 VPN, for special applications. 

Sol-gel techniques have been widely used to prepare ceramic or glass materials with controlled microstructures. Applications of the sol-gel method in fabrication of high-temperature fuel cells are steadily reported. Modification of electrodes, electrolytes or electrolyte/electrode interface of the fuel cell has been also performed to produce components with improved microstructures. Recently, the sol-gel method has expanded into inorganic-organic hybrid membranes for low-temperature fuel cells. This paper presents an overview concerning current applications of sol-gel techniques in fabrication of fuel cell components. 

The above brief analysis underlines that the porous structure of the carbon substrate and the presence of an ionomer impose limitations on the application of porous and thin-layer RDEs to studies of the size effect. Unless measurements are carried out at very low currents, corrections for mass transport and ohmic limitations within the CL [Gloaguen et ah, 1998 Antoine et ah, 1998] must be performed, otherwise evaluation of kinetic parameters may be erroneous. This is relevant for the ORR, and even more so for the much faster HOR, especially if the measurements are performed at high overpotentials and with relatively thick CLs. Impurities, which are often present in technical carbons, must also be considered, given the high purity requirements in electrocatalytic measurements in aqueous electrolytes at room temperature and for samples with small surface area. 

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