2023/03/19 by Se‐Ho Kim, Kim, Se-Ho, Hosun Jun +9 · 1 citation
Energy · Engineering · #Advanced Materials Characterization Techniques #Electrocatalysts for Energy Conversion #FOS: Physical sciences #Fuel Cells and Related Materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2303.10548
openalex publication_date 2023/03/19 · openalex created_date 2023/03/22 · openalex updated_date 2026/07/28
Proton exchange membrane fuel cells hold promise as energy conversion devices for hydrogen-based power generation and storage. However, the slow kinetics of the oxygen reduction at the cathode imposes the need for highly active catalysts, typically Pt or Pt-based, with a large available area. The scarcity of Pt increases deployment and operational cost, driving the development of novel highly-active material systems. As an alternative, Rh-doped PtNi nanoparticle has been suggested as promising oxygen reduction catalyst, but the 3D distributions of constituent elements in the nanoparticles have remained unclear, making it difficult to guide property optimization. Here, a combination of advanced microscopy and microanalysis techniques is used to study the Rh distribution in the PtNi nanoparticles, and Rh surface segregation is revealed, even with an overall Rh content below 2 at. %. Our findings suggest that doping and surface chemistry must be carefully investigated to establish a clear link with catalytic activity can truly be established.