Proton exchange membrane fuel cell advantages

This survey focuses on recent developments in catalysts for phosphoric acid fuel cells (PAFC), proton-exchange membrane fuel cells (PEMFC), and the direct methanol fuel cell (DMFC). In PAFC, operating at 160-220°C, orthophosphoric acid is used as the electrolyte, the anode catalyst is Pt and the cathode can be a bimetallic system like Pt/Cr/Co. For this purpose, a bimetallic colloidal precursor of the composition Pt50Co30Cr20 (size 3.8 nm) was prepared by the co-reduction of the corresponding metal salts [184-186], From XRD analysis, the bimetallic particles were found alloyed in an ordered fct-structure. The elecbocatalytic performance in a standard half-cell was compared with an industrial standard catalyst (bimetallic crystallites of 5.7 nm size) manufactured by co-precipitation and subsequent annealing to 900°C. The advantage of the bimetallic colloid catalysts lies in its improved durability, which is essential for PAFC applicabons. After 22 h it was found that the potential had decayed by less than 10 mV [187],... 

The held to which the specific features of CNTs and CNFs could bring the most significant advancements is perhaps that of fuel cell electrocatalysis [125,187]. The main uses of CNTs or CNFs as catalyst support for anode or cathode catalysis in direct methanol fuel cells (DMFCs) or proton-exchange membrane fuel cells (PEMFCs) are covered in Chapter 12. In this section we summarize the main advantages linked to the use of nanotubes or nauofibers for these applications. 

The practical advantage of this compound is its safety when stored or delivered as a powder or liquid. The quality of water is not a serious issue and any water, such as rain, underground, river, waste, or seawater, is suitable when it is used to make liquid solutions for supplying hydrogen to actuate proton exchange membrane fuel cells (PEMFCs) in emergency and portable uses. 

Sulfonated PPESK membrane materials have been demonstrated to be useful for various types of fuel cells, such as formic acid fuel cells, and methanol fuel cells. The direct methanol fuel cell has certain advantages over the proton exchange membrane fuel cell because it is more suitable for portable applications. Because of the interest in these cells, many papers focus on materials suitable for membranes. The reactions in a direct methanol fuel cell are ... 

Alkaline fuel cells have numerous advantages over proton exchange membrane fuel cells on both cathode kinetics and ohmic polarization [115]. 

Using proton exchange membranes as electrolytes that are quasi-solid may cause a problem with respect to the perfect wetting of the catalyst particles. In spite of this (initial) difficulty of developing solid polymer membrane fuel cells, water-swollen perfluorinated sulfonic acid polymers such as the commercial Nation have been used for fuel cells very early since they offer the following advantages ... 

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