In anion exchange membrane fuel cells, Pd nanoparticles are extensively studied as promising non-Pt catalysts due to their electronic structure similar to Pt. In this study, to fabricate Pd nanoparticles well dispersed on carbon support materials, we propose a synthetic strategy using mixed organic ligands with different chemical structures and functions. Simultaneously to control the Pd particle size and dispersion, a ligand mixture composed of oleylamine(OA) and trioctylphosphine(TOP) is utilized during thermal decomposition of Pd precursors. In the ligand mixture, OA serves mainly as a reducing agent rather than a stabilizer since TOP, which has a bulky structure, more strongly interacts with the Pd metal surface as a stabilizer compared to OA. The specific roles of OA and TOP in the Pd nanoparticle synthesis are studied according to the mixture composition, and the oxygen reduction reaction(ORR) activity and durability of highly-dispersed Pd nanocatalysts with different particles sizes are investigated. The results of this study confirm that the Pd nanocatalyst with large particles has high durability compared to the nanocatalyst with small Pd nanoparticles during the accelerated degradation tests although they initially indicated similar ORR performance.

Abstract
 1. 서 론
 2. 실험 방법
 3. 결과 및 고찰
 4. 결 론
 Reference

• 성후광(충남대학교 에너지과학기술대학원) | Hukwang Sung (Graduate School of Energy Science and Technology, Chungnam National University)
• Monika Sharma(충남대학교 에너지과학기술대학원)
• 장정희(충남대학교 에너지과학기술대학원) | Jeonghee Jang (Graduate School of Energy Science and Technology, Chungnam National University)
• 정남기(충남대학교 에너지과학기술대학원) | Namgee Jung (Graduate School of Energy Science and Technology, Chungnam National University) Corresponding author