Electrodes and Catalysts

In a typical design, the electrodes can contain high loadings of noble metals for low-temperature operation (80°C to 90°C). For example, electrodes made 

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In a fuel cell, chemical energy is converted into electrical energy. For instance, in an H2-02 fuel cell (Fig. 13.4), porous electrodes and catalyst layers are separated by a SPE membrane (e.g. Nation 117). 

ECN Holland works on both the SOFC and PEMFC. For the PEMFC its web site asserts the imminence of breakthroughs in materials development. ECN is active in electrolyte development, electrode and catalyst development, and stack development. No description is given of the detail design features. 

Industrially, the great application of ORMEs is as an electrode and catalyst material for fuel cells. In a few years fuel cells are destined to replace batteries in everything from mobile phones to automobiles. The market for fuel cells will be enormous and their use is only being held back by the lack of a suitable electrode material. The special characteristic of ORMEs is that it is a superconductor and therefore suitable as an electrode material. This was in fact the specific basis that the US Defense Department vetoed David Hudson s US patent application. 

REVIEW OF DIRECT METHANOL FUEL CELL ELECTRODES AND CATALYST... 

In the electrocatalytic membrane reactor, the reactions normally take place at the electrodes. This means that the electrode should act as both electrode and catalyst. As an electrode, high electronic conductivity is required. In general, the electronic conductivity of electrode materials should not be less than 10 S/cm at the operating temperature. As a catalyst, the material must have good catalytic activity for the corresponding reactions. 

Haas HR, Davis MT (2009) Electrode and catalyst durability requirements in automotive PEM applications technology status of a recent MEA design and next generation challenges. ECS Trans 25 1623-1631... 

Source E-TEK. Gas Diffusion Electrodes and Catalyst Materials catalog, 1995 Marr, C., X. Li, 1999. Journal of Power Sources, 77 V7-27. With permission. 

Haas H and Davis M (2009), Electrode and Catalyst Durability Requirements in Automotive PEM Applications Technology Status of a Recent MEA Design and Next Generation Challenge , i C5 Transactions, 25,1,1623-1631. 

The scale-up and integration of multiple air-breathing fuel cells, while ensuring sufficient oxidant access, can be complicated by geometrical restrictions. INI Power Systems (Morrisville, NC) is developing a direct methanol microfluidic fuel cell system with integrated gas diffusion cathode for commercial applications. Notably, recent improvements of electrodes and catalysts, optimization of methanol concentration and flow rates, and the addition of a gaseous flow field on the cathode side have resulted in impressive power densities on the order of 100 mW cm [42], As compared to conventional MEA-based direct methanol fuel cells, these microfluidic fuel cells are competitive. 

Noncalssical crystallization has attracted much interest in recent years. In classical models, crystalline materials were classified into single crystal and polycrystal. A variety of recent reports have showed mesocrystals as the intermediate states between single crystal and polycrystal. The present report focuses on mesocrystals and their related architectures consisting of the unit crystals. A variety of mesocrystals and their related architectures were categorized by the ordered state of the unit crystals. These new superstructures have potentials for a variety of applications, such as electrode and catalyst materials. 

Electrode kinetics, electrode and catalysts surface area -Microstructure Spectroscopy-Auger Electron (AES), x-ray photoelectron (XPS), secondary ion mass spectroscopy (SIMS) -Chemical identification ... 

In this study porous electrode and catalyst layers were applied on both surfaces of the membrane to enhance surface exchange rates. 

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