Evaluation of Pt−Au/MWCNT (Multiwalled Carbon Nanotubes) electrocatalyst performance as cathode of a proton exchange membrane fuel cell

A comparative study between Pt−Au/MWCNT and Pt/C (commercial) as cathodic electrocatalyst of H₂/O₂ fuel cell is performed. Pt−Au/MWCNT is synthesized using the reverse microemulsion method and this procedure is scaled-up in order to prepare membrane-electrode assemblies for fuel cells with an active area of 9 cm². Those electrocatalysts are characterized by both physicochemical techniques and electrochemical measurements to evaluate their catalytic activity for ORR (Oxygen Reduction Reaction). In the half-cell study, Pt−Au/MWCNT show higher kinetic current density as cathodic electrocatalyst compared with Pt/C. Likewise, in a fuel cell hardware the maximum power density is significantly higher for Pt−Au/MWCNT cathode (625 mW cm⁻² at 0.426 V) when compared with Pt/C anode (355 mW cm⁻² at 0.499 V). - Highlights: • Pt−Au/MWCNT was synthesized by reverse microemulsión method. • Pt−Au/MWCNT and Pt/C were characterized by microscopic and spectroscopic techniques. • Both materials were studied as catalysts for ORR by electrochemical techniques. • Catalysts were used to prepare MEA's, the performance in fuel cell was evaluated. • Maximum power densities were 625 mW cm⁻² for Pt−Au/MWCNT and 355 mW cm⁻² for Pt/C.