Elucidation of durability of carbon-supported PdIr alloy catalyst by experimental and theoretical approaches in polymer electrolyte membrane fuel cell

• Published in: Journal of industrial and engineering chemistry (Seoul, Korea) Vol. 97; pp. 280 - 286
• Main Authors: Kwon, Kyungjung, Lee, Kang Hee, Um, Dong Ho, Jin, Seon-ah, Park, Hyun S., Cho, Jinwon, Hyun, Jinho, Ham, Hyung Chul, Pak, Chanho
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 25.05.2021; 한국공업화학회
• Subjects: Density functional theory; Membrane electrode assembly durability; Oxygen reduction reaction; PdIr alloy catalyst; Polymer electrolyte membrane fuel cell; 화학공학; PdIr alloy catalyst; Membrane electrode assembly durability; Density functional theory; Polymer electrolyte membrane fuel cell; Oxygen reduction reaction
• ISSN: 1226-086X; 1876-794X
• DOI: 10.1016/j.jiec.2021.02.013

[Display omitted] PdIr nanoparticles supported on carbon support are synthesized and their oxygen reduction reaction (ORR) activity and durability in a half cell or membrane-electrode assembly (MEA) configuration for polymer electrolyte membrane fuel cell are examined. A synergistic effect of the combination of Pd possessing the effective ORR catalytic activity and Ir as one of the most stable elements in acidic media leads to a decrease in particle size, a higher particle dispersion, and a better ORR activity than Pd monometallic catalysts. It is expected that PdIr alloys would form phase-separated nanoalloys that have Pd-rich surface owing to the higher surface energy of Ir. The addition of Ir to Pd in PdIr/C increases the metallic Pd portion. Meanwhile, the Pd5Ir/C is the most durable compared to Pd/C and Pt/C over 3000h of MEA operation. The ORR activity of PdIr alloy is expected to increase by reducing the oxygen binding energy of Pd in the presence of Ir from the first-principle calculation, and each contribution of compressive strain and ligand effects is quantified. The cohesive energy and the kinetic segregation energy are also calculated to support the improved stability of PdIr compared to Pd and Pt in the ORR condition.