Injoon Jang Ahn, Minjeh Lee, Sehyun Yoo, Sung Jong 2024-01-12T03:02:04Z 2024-01-12T03:02:04Z 2023-01-04 2022-06 1226-086X https://pubs.kist.re.kr/handle/201004/76691 The alloying strategy of Pt with Ni is commonly employed to improve the catalytic activity of electrocatalysts owing to the higher activity required to lower the binding energy of oxygen with Pt. When Pt is alloyed with Ni, electron transfer from Ni to Pt is conducive to metallic Pt, lowering the oxygen binding energy. Although the alloying strategy can increase the catalytic activity, confirming that the surface state has the intended electronic structure is difficult because of the oxidation or dissolution of metals. To determine the surface state of catalyst nanoparticles for a more efficient structure, the concept of physical blocking of the reactive surface was applied to determine the geometric effect. The oxygen reduction reaction in phosphoric acid electrolytes is more sensitive to the geometric effect due to anion adsorption. In this work, we synthesized carbon-supported PtNi alloying nanoparticles with different carbon shell thicknesses (PtNi@Cx; x = 0.5, 1, 2, 4, where x refers to the concentration of the surfactant) from various concentration of organic surfactants. Among the nanoparticles with various carbon shell thicknesses, PtNi@C2 showed the best oxygen reduction reaction performance in the presence of phosphoric acid with an appropriate geometric effect, ensuring a synergetic effect with alloying.(c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved. English ELSEVIER SCIENCE INC Surfactant assisted geometric barriers on PtNi@C electrocatalyst for phosphoric acid fuel cells Article 10.1016/j.jiec.2022.02.055 1 JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY, v.110, pp.198 - 205 JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY 110 198 205 N scie scopus kci 000802131500004 Chemistry, Multidisciplinary Engineering, Chemical Chemistry Engineering OXYGEN REDUCTION REACTION ALLOY ELECTROCATALYSTS TEMPERATURE MEMBRANE OLEYLAMINE CATALYST METAL POLYBENZIMIDAZOLE NANOCATALYSTS STABILITY Phosphoric acid fuel cell Electrocatalysts Oxygen reduction reaction Pt-Ni metal alloy Carbon shell Geometric effect