A casting combined quenching strategy to prepare PdAg single atom alloys designed using the cluster expansion combined Monte Carlo method. Issue 4 (11th January 2022)

• Record Type: Journal Article
• Authors: Hua, Minghao; Tian, Xuelei; Li, Shuo; Zhang, Xiaofu; Shao, Anchen; Song, Lin; Lin, Xiaohang
• Is Part Of: Physical chemistry chemical physics. Volume 24:Issue 4(2022)
• Page Start: 2251
• Page End: 2264
• Publication Date: 2022-01-11
• Subjects: Chemistry, Physical and theoretical -- Periodicals; 541.3
• DOI: 10.1039/d1cp05046j
• Languages: English
• ISSNs: 1463-9076

Abstract

Abstract : Both cluster expansion based Monte Carlo simulations and experiments show the presence of Ag on the surfaces of PdAg alloys prepared using casting combined quenching processes; Pd atoms are uniformly dispersed to form single atom alloys. Abstract : In this work, the surface structure of a PdAg alloy is investigated by cluster expansion (CE) combined Monte Carlo (MC) simulations. All systems with different component proportions show an obvious component segregation corresponding to the depth from the surface. A significant amount of Ag is observed on the first layer, and Pd is concentrated significantly on the second layer. The Pd distribution on the PdAg surfaces is closely related to the temperature and composition ascribed to the concentration and configurational entropy effects, which are explicitly treated in MC simulations. The vacancies mainly distribute separately. The simulation results show good agreement with the experimental evidence. Moreover, we demonstrated a general and highly effective casting combined quenching strategy for controlling the ensemble size and chemical composition of alloy surfaces which could successfully be applied to the large-scale production of SAA.