Titanate electrolytes

TABLE 4. Phase structure of titanic electrolytic powders after corrosion in 5 % a solution HC1 (the X-ray phases analysis)... 

Emery J, Buzare JY, Bohnke O et al (1997) Llthlum-7 NMR and Ionic conductivity studies of lanthanum lithium titanate electrolytes. Solid State Ionics 99 41-51... 

Titanium Sulfates. Solutions of titanous sulfate [10343-61-0] ate readily made by reduction of titanium(IV) sulfate ia sulfuric acid solutioa by electrolytic or chemical means, eg, by reduction with ziac, ziac amalgam, or chromium (IT) chloride. The reaction is the basis of the most used titrimetric procedure for the determination of titanium. Titanous sulfate solutions are violet and, unless protected, can slowly oxidize ia coatact with the atmosphere. If all the titanium has been reduced to the trivalent form and the solution is then evaporated, crystals of an acid sulfate 3 Ti2(S0 2 [10343-61-0] ate produced. This purple salt, stable ia air at aormal temperatures, dissolves ia water to give a stable violet solutioa. Whea heated ia air, it decomposes to Ti02, water, sulfuric acid, and sulfur dioxide. 

In the ceramics field many of the new advanced ceramic oxides have a specially prepared mixture of cations which determines the crystal structure, through the relative sizes of the cations and oxygen ions, and the physical properties through the choice of cations and tlreh oxidation states. These include, for example, solid electrolytes and electrodes for sensors and fuel cells, fenites and garnets for magnetic systems, zirconates and titanates for piezoelectric materials, as well as ceramic superconductors and a number of other substances... 

Mkaline Fuel Cell The electrolyte for NASA s space shnttle orbiter fuel cell is 35 percent potassinm hydroxide. The cell operates between 353 and 363 K (176 and I94°F) at 0.4 MPa (59 psia) on hydrogen and oxygen. The electrodes contain platinnm-palladinm and platinum-gold alloy powder catalysts bonded with polytetraflnoro-ethylene (PTFE) latex and snpported on gold-plated nickel screens for cnrrent collection and gas distribution. A variety of materials, inclnding asbestos and potassinm titanate, are used to form a micro-porous separator that retains the electrolyte between the electrodes. The cell structural materials, bipolar plates, and external housing are nsnally nickel-plated to resist corrosion. The complete orbiter fuel cell power plant is shown in Fig. 24-48. 

Figure 5. Mutual influence of oxygen and hydrogen on hardness of electrolytic titanic powders.

Instead of the system silica/silicate also other systems such as titania/titanate, zirconia/zirconate can be used as a reference system [xiv]. The response time of freshly fabricated thick-film sensors based on thin-film /3-alumina is very short (about 15 ms at 650 °C). After several weeks of operating this time increases 10 times (150 ms) [xv]. Solid electrolyte C02 sensors using Ni/carbonate composite as measuring electrode are suited for measuring of C02 in equilibrated water gases [xiv]. Using semiconducting oxides and carbonates like ITO (indium tin oxide) Nasicon-based C02 sensors are able to measure at room temperature [xvi]. 

Photocatalytic and Photoelectrochemical Hydrogen Production on Strontium Titanate Single Crystals. Both metal-free and platinized samples studied in aqueous alkaline electrolytes or in the presence of NaOH-coated crystals. 391... 

MgFj solid electrolytes have also been used to measure activities of MgO in both compounds (Magnesium Titanates - Shah et al, 1970) and solid solutions involving MgO. In the latter category, MgO-ZnO, MgO-CoO and MgO-NiO have been studies by Raghavan et al. (1975) and Prasad (1971). Seetharaman (1970) has rechecked some of the results. He found very good agreement in results obtained from the different techniques. 

Ballard Power Systems of Canada (see web site) is the Titan, the co-ordinating major force in the international proton exchange fuel cell or polymer electrolyte fuel cell (PEFC) business. Ballard claims over 500 patents Also, a worldwide complex of allies serves its international interests. 

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