NEW INSIGHT INTO MICROSCALE TRANSPORT PHENOMENA IN PEFC BY QUANTUM MD

Polymer electrolyte fuel cells (PEFCs) are among the most promising energy equipment options because of its high power density and efficiency; however, there are numerous technical problems to commercialize this technique, and understanding the critical phenomena for the performance of PEFC is essential. We performed the molecular simulation study about oxygen reduction reaction on the cathode catalyst and mass transport in the polymer electrolyte. We performed two kinds of simulations based on the first principle's molecular dynamics to elucidate oxygen reduction reaction, the finite temperature simulation of oxygen reduction reaction on the clean platinum surface, and the energy minimization simulation of oxygen adsorption on the various transition metals. We acquired novel information concerning the mechanism of oxygen reduction reaction, and it was found that one of the most critical factors for the catalysis was the oxygen adsorption structure on the clean platinum surface. We also employed the molecular dynamics study of mass transport in the polymer electrolyte. It successfully reproduced the experimental results. Moreover, we acquired information about the molecular scale structure and the transport mechanism in the polymer electrolyte. We proposed guiding principles for designing high conductive electrolytes based on these results.