Impact of catalyst structure and synthesis route on the ORR performance of Pt-Co3O4/C catalysts for PEM fuel cells

Abstract

The development of high-performance cathode catalysts remains a challenge for proton exchange membrane (PEM) fuel cells. In this study, the effect of catalyst configuration was investigated using Co3O4-based supports for Pt. Two catalyst structures were prepared: Pt nanoparticles directly deposited on Co3O4 (Pt@Co3O4/C) and Pt nanoparticles supported on carbon-coated Co3O4 (Pt/Co3O4@C). Structural characterization indicates that the Pt/Co3O4@C catalyst exhibits a more homogeneous Pt distribution and higher Pt loading, resulting in an increase in electrochemically active surface area (ECSA) from 74 to 137 m(2)g(-1)Pt compared to Pt@Co3O4/C. Durability evaluation based on ECSA retention after 1000 potential cycles shows improved stability for Pt/Co3O4@C (55%) compared to Pt@Co3O4/C (36%). In single-cell PEM fuel cell tests, the Pt/Co3O4@C catalyst achieves a higher maximum power density of 109 mWcm(-2) at 80 degrees C, compared to 73.2 mWcm(-2) for Pt@Co3O4/C. These results suggest that interfacial and structural features, together with Pt loading, contribute to improved fuel cell performance.