Alloy electrode materials

Mechanical alloying (MA) has proved to be an effective method to synthesize and modify the hydrogen storage alloy electrode materials [13, 14, 19-21], Zaluski et al. [22] studied the catalytic effect... 

At the Zinc Lead 9S Symposium, Koike et al. (1) reported that the anode potential decreases when Ca was added to the conventional Pb-Ag alloy electrode material and also when alcohol was added as a depolarizing substance in the electrolyte. 

An Li-Al Alloy was investigated for use as a negative electrode material for lithium secondary batteries. Figure 41 shows the cycle performance of a Li-Al electrode at 6% depth of discharge (DOD). The Li-Al alloy was prepared by an electrochemical method. The life of this electrode was only 250 cycles, and the Li-Al alloy was not adequate as a negative material for a practical lithium battery. 

There are few systematic guidelines which can be used to predict the properties of AB2 metal hydride electrodes. Alloy formulation is primarily an empirical process where the composition is designed to provide a bulk hydride-forming phase (or phases) which form, in situ, a corrosion— resistance surface of semipassivating oxide (hydroxide) layers. Lattice expansion is usually reduced relative to the ABS hydrides because of a lower VH. Pressure-composition isotherms of complex AB2 electrode materials indicate nonideal behaviour. 

The recent development of the convertible oxide materials at Fuji Photo Film Co. will surely cause much more attention to be given to alternative lithium alloy negative electrode materials in the near future from both scientific and technological standpoints. This work has shown that it may pay not only to consider different known materials, but also to think about various strategies that might be used to form attractive materials in situ inside the electrochemical cell. 

From a thermodynamic point of view, apart from charge density and specific charge, the redox potential of lithium insertion into/removal from the electrode materials has to be considered also. For instance, the redox potential of many Li alloys is between -0.3 and -1.0 V vs. Li/Li+, whereas it is only -0.1 V vs. 

Ruthenium nowadays finds many uses in the electronics industry, particularly for making resistor tracks. It is used as an ingredient in various catalysts and, importantly, in electrode materials, e.g. Ru02-coated titanium elements in the chloralkali industry. Osmium tetroxide is a very useful organic oxidant and, classically, is used as a tissue stain. Both elements are employed in making certain platinum alloys. 

Electrode-concentration is based on dilution of the electrode material itself. For the electrode material to be engaged in such a process, it must have a changeable concentration. Amalgams or alloy electrodes with different concentrations of solute metal, and gas elec-... 

The catalytic properties of a Pt/Sn combination were observed on different kinds of electrode materials alloys [90], electro co-deposits of Pt and Sn [89, 90], underpotential deposited tin [42] or a mixture of tin oxide and platinum deposited on glass [95], All different materials present a marked influence on methanol electrooxidation. 

Anani A., Crouch-Baker S., Huggins RA. Kinetic and Thermodynamic Properties of Several Binary Lithium Alloy Negative Electrode Materials at Ambient Temperature. J. Electrochem. Soc. 1987 134 3098-101. 

Mono- or single-crystal materials are undoubtedly the most straightforward to handle conceptually, however, and we start our consideration of electrochemistry by examining some simple substances to show how the surface structure follows immediately from the bulk structure we will need this information in chapter 2, since modern single-crystal studies have shed considerable light on the mechanism of many prototypical electrochemical reactions. The great majority of electrode materials are either elemental metals or metal alloys, most of which have a face-centred or body-centred cubic structure, or one based on a hexagonal close-packed array of atoms. 

For the simplest analyses of metals and alloys, electrodes made of the sample material itself may be used, a disc or cylinder being cut, cast or... 

Unlike the constraints on anode material, the constraints on cathode materials are usually lower because typically they do not need to constitute the transparent electrode material. In certain instances, where a completely transparent OLED is needed (windshield and heads-up displays), ITO may also be used as the cathode with suitable modification [12]. In general, cathode materials are pure metals or metal alloys. The requirements for cathode materials are as follows ... 

The behavior of Pt and other alloy electrocatalyst crystallites used as the electrode materials for phosphoric acid electrolyte fuel-cells. 

L.Chen, F.Wu, M.Tong et al. Advanced nanocrystalline Zr-based AB2 hydrogen storage electrode materials for NiMH EV batteries. Journal of alloys and compounds, 293-295, 508-520 (1999)... 

The data in Table 6-1 provide a chronology of the evolution in cell component technology for MCFCs. In the mid-1960s, electrode materials were, in many cases, precious metals, but the technology soon evolved to the use of Ni-based alloys at the anode and oxides at the cathode. 

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