Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)In this work Pt-Ru/C catalysts are prepared in different atomic ratios by reduction with formic acid and submitted to thermal treatment in a hydrogen atmosphere. Physical characterisation of the materials by XRD, EDX, and TEM shows that the particle site increases as a consequence of the thermal treatments and this effect is relevant in the electrochemical behaviour of these materials in a DMFC. Finally, the performance of the DMFC with different flow fields is examined.241732159165Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)FAPESP [98/12922-8).]