the electrocatalysis of the oxygen reduction reaction (orr) on carbon supportedpt-v (1:1) catalyst in polymer electrolyte fuel cells (pefc) was investigated. atan oxygen pressure of one atm an enhanced electrocatalytic property of pt-v/ccompared with pt/c is revealed. these results indicate the occurrence of adifferent electrocatalytic mechanism for the orr on pt/c and pt-v/c. anincrease of mas...

the electrocatalysis of the oxygen reduction reaction (orr) on carbon supportedpt-v (1:1) catalyst in polymer electrolyte fuel cells (pefc) was investigated. atan oxygen pressure of one atm an enhanced electrocatalytic property of pt-v/ccompared with pt/c is revealed. these results indicate the occurrence of adifferent electrocatalytic mechanism for the orr on pt/c and pt-v/c. anincrease of mas...

In a polymer membrane fuel cell more than half of the chemical energy of hydrogen is converted to heat during generation of electricity. This causes an increase in the cell temperature. The Cooling field design has a significant role in cell cooling. The cell's performance and stability are reduced due to inappropriate heat dissipation. In this paper, the cooling flow and heat transfer in cooli...

Contact resistance among the components of a polymer exchange membrane fuel cell (PEMFC) has a crucial effect on cell performance. The geometry of the endplate plays an essential role in the contact pressure distribution over the membrane electrode assembly (MEA) and the amount of contact resistance between plates. In this work, the effects of endplate geometry on the contact pressure distribut...

sulfonated poly (ether ether ketone) (speek) with a low degree of sulfonation (ds = 40%) was prepared for proton exchange membrane fuel cells (pemfc). poly (ether ether ketone) (peek) was sulfonated in concentrated h2so4 under n2 atmosphere and characterized by the hydrogen nuclear magnetic resonance (h-nmr) technique. after preparation of the speek polymer, the obtained polymer was dissolved i...

Reformate gas, a commonly employed fuel for polymer electrolyte membrane fuel cells (PEMFCs), contains carbon monoxide, which poisons Pt-containing anodes in such devices. A novel, low-cost mesoporous Si3N4 selective gas separation material was tested as a hydrogen clean-up membrane to remove CO from simulated feed gas to single-cell PEMFC, employing Nafion as the polymer electrolyte membrane. ...

“Ignition/extinction” phenomena and steady-state multiplicity were discovered in an autohumidi$cation polymer electrolyte membrane fuel cell. At steady state, the water produced by the fuel cell reaction is balanced by water removal by the 7owing reactant gas streams. Ignition, corresponding to a high fuel cell current, arises from positive feedback between the water produced by the reaction an...