Kim, Chang-Eun Lim, Dong-Hee Jang, Jong Hyun Kim, Hyoung Juhn Yoon, Sung Pil Han, Jonghee Nam, Suk Woo Hong, Seong-Ahn Soon, Aloysius Ham, Hyung Chul 2024-01-20T08:01:14Z 2024-01-20T08:01:14Z 2021-09-04 2015-01-21 0021-9606 https://pubs.kist.re.kr/handle/201004/125857 The effect of a subsurface hetero layer (thin gold) on the activity and stability of Pt skin surface in Pt3M system (M = 3d transition metals) is investigated using the spin-polarized density functional theory calculation. First, we find that the heterometallic interaction between the Pt skin surface and the gold subsurface in Pt/Au/Pt3M system can significantly modify the electronic structure of the Pt skin surface. In particular, the local density of states projected onto the d states of Pt skin surface near the Fermi level is drastically decreased compared to the Pt/Pt/Pt3M case, leading to the reduction of the oxygen binding strength of the Pt skin surface. This modification is related to the increase of surface charge polarization of outmost Pt skin atoms by the electron transfer from the gold subsurface atoms. Furthermore, a subsurface gold layer is found to cast the energetic barrier to the segregation loss of metal atoms from the bulk (inside) region, which can enhance the durability of Pt3M based catalytic system in oxygen reduction condition at fuel cell devices. This study highlights that a gold subsurface hetero layer can provide an additional mean to tune the surface activity toward oxygen species and in turn the oxygen reduction reaction, where the utilization of geometric strain already reaches its practical limit. (C) 2015 AIP Publishing LLC. English AMER INST PHYSICS OXYGEN REDUCTION REACTION TOTAL-ENERGY CALCULATIONS AUGMENTED-WAVE METHOD FUEL-CELLS ELECTRONIC-STRUCTURE BIMETALLIC SURFACES BASIS-SET PT-SKIN ELECTROCATALYSTS PLATINUM Effect of gold subsurface layer on the surface activity and segregation in Pt/Au/Pt3M (where M=3d transition metals) alloy catalyst from first-principles Article 10.1063/1.4905919 1 JOURNAL OF CHEMICAL PHYSICS, v.142, no.3 JOURNAL OF CHEMICAL PHYSICS 142 3 scie scopus 000348302900043 2-s2.0-84923807543 Chemistry, Physical Physics, Atomic, Molecular & Chemical Chemistry Physics Article OXYGEN REDUCTION REACTION TOTAL-ENERGY CALCULATIONS AUGMENTED-WAVE METHOD FUEL-CELLS ELECTRONIC-STRUCTURE BIMETALLIC SURFACES BASIS-SET PT-SKIN ELECTROCATALYSTS PLATINUM ORR Au Pt3M segregation