Comparative Analysis of Durability and Performance of High-Loaded Pt Catalysts on Various Carbon Supports Using Electron Beam Reduction for Fuel Cells

Abstract

Carbon supports are important for the improved utilization of Pt nanoparticles (NPs), pore formation, and increased electrical conductivity in polymer electrolyte membrane fuel cells. This study uses electron-beam irradiation–reduction, which is a reductant-free catalyst-synthesis method with a fast synthesis time that is easy to scale up for mass production, to synthesize highly loaded and well-dispersed catalysts with 60 wt % of Pt NPs. The supports are prepared as commercial furnace black (EC-300J), acetylene black (Vinatech carbon black; VINA), and mesoporous carbon (MH18). In a half-cell, Pt/VINA displayed outstanding overall electrochemical performance; in particular, its electrochemical surface area (ECSA) has an average value of ∼24.6% higher than that of either of the other two catalysts. In catalyst-durability tests, the change in half-potential at 0.9 V_RHE is lower for Pt/VINA (−17.5%) than for either Pt/EC-300J (−25.2%) or Pt/MH18 (−33.9%). Similar results are obtained in single-cell catalyst-durability tests. The durability of the carbon support, evaluated in a single-cell test, shows that Pt/EC-300J exhibits the largest reduction in ECSA (−40.1%), followed by Pt/VINA (−28.9%) and Pt/MH18 (−26.2%). The electrode thickness of the highly crystalline Pt/VINA decreases by only −52.4%, while those of the Pt/EC-300J and Pt/MH18 electrodes are reduced by −66.1 and −60.9%, respectively. Interestingly, Pt/MH18 initially performed poorly due to the bulky carbon supports with narrow pore sizes, which resulted in agglomeration of the catalyst. After the support-durability test, however, the structure of this electrode remained well-maintained and exhibited excellent performance.