Membrane technology PEMFCs catalysts

In PEMFCs working at low temperatures (20-90 °C), several problems need to be solved before the technological development of fuel cell stacks for different applications. This concerns the properties of the components of the elementary cell, that is, the proton exchange membrane, the electrode (anode and cathode) catalysts, the membrane-electrode assemblies and the bipolar plates [19, 20]. This also concerns the overall system vdth its control and management equipment (circulation of reactants and water, heat exhaust, membrane humidification, etc.). 

PEMFC R D areas include slightly higher temperature (120°C) and lower cost membrane materials, resistant and low-cost catalyst materials, long life. The technology must meet all the basic criteria for performance, durability and cost. Examples of projects include ... 

DMFCs are PEMFCs fed with methanol as fuel. The technologies required by DMFCs are similar to those of PEMFCs. What differ between DMFCs and PEMFCs are in the following two aspects The proton exchange membrane used for DMFCs must possess low methanol permeability or crossover, and the anode catalyst must possess high activity toward the oxidation of methanol and high tolerance to CO and other intermediates from methanol oxidation. In this section, the applications of NMR techniques for the development of DMCFs as well as essential materials are going to be briefly reviewed. 

A PEMFC uses a solid membrane that conducts protons as the electrolyte. Since it can start at ambient temperatures instantly, it is ideal for backup, portable, and motive power applications. The most important technologies concern the stack (like the heart of a human being) and the system controls (like the brain of a human being). The key components in a stack include the catalyst, PEM, GDM, plates, and gasket, while the controls include the operation algorithm, software, and electronic circuits. A fuel cell also needs various auxiliary components such as fans, blowers, compressors, pumps, heat exchangers, humidifiers, converters, valves, sensors, and batteries to work. A fuel cell system involves multidisciplinary skills and knowledge, and therefore it requires a team effort to develop. 

Wuhan University of Technology A Chinese key state university with a total student enrollment of more than 52,700. It was established in 2000 by combining three local universities. Wuhan University of Technology is a leading Chinese university in developing catalyst-coated membranes (CCMs) for PEMFCs. It is located in Wuhan, Hubei, China. University website http //www.whut.edu.cn. 

Development of high-temperature proton exchange membranes and catalysts for HT-PEMFCs are equally important in terms of the long-term sustainability of fuel cell technology and commercialization. Based on a review of the literature as well as our understanding, we would like to suggest several future research topics for high-temperature catalyst development ... 

Table 22.2. Carbon blacks that have been used as support for Pt catalysts in PEMFCs [3]. (Reproduced from Thompsett D. Catalysts for the proton exchange membrane fuel cell. In Hoogers G, editor. Fuel cell technology handbook. Boca Raton CRC Press, 2003. With permission from CRC.)...

---