title: Controlled Synthesis of Octahedral Platinum-Based Mesocrystals by Oriented Aggregation.
abstract: Designed synthesis of noble metal mesocrystals is of great significance for a variety of applications. Here, the synthesis of octahedral Pt-Ag alloy mesocrystals with precisely controlled morphology, size, and exposing facets, formed by oriented aggregation of their crystallites, is reported. The critical role of bromide was revealed in regulating the overall octahedral morphology of the Pt-Ag mesocrystals, by bridging the interactions between the capping agent and the Ag-modified Pt crystallites. The size of the mesocrystals was precisely controlled in a broad range by tuning the number of the seeds, all retaining their octahedral morphology. Based on this understanding, octahedral Pt-Ag mesocrystals exposing {1 1 1} facets have been obtained in a highly controllable and reproducible manner. This material showed excellent electrocatalytic activity and stability in oxygen reduction reactions (ORR). It is hoped that the current synthesis provides new insights that pave the way to diverse faceted nanocrystals/mesocrystals for high-performance catalytic and many other applications.
authors.affiliation: Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710054, P. R. China.
authors.forename: Ping
authors.initials: P
authors.lastname: Zhong
authors.affiliation: Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710054, P. R. China.
authors.forename: Hongpo
authors.initials: H
authors.lastname: Liu
authors.affiliation: School of Science, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, P. R. China.
authors.forename: Jie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Department of Chemistry, University of California, Riverside, California, 92521, USA.
authors.forename: Yadong
authors.identifier: http://orcid.org/0000-0003-0218-3042
authors.initials: Y
authors.lastname: Yin
authors.affiliation: Frontier Institute of Science and Technology, Xi'an Jiaotong University, Xi'an, Shaanxi, 710054, P. R. China.
authors.forename: Chuanbo
authors.identifier: http://orcid.org/0000-0003-3429-3473
authors.initials: C
authors.lastname: Gao
keywords: electrocatalysis; mesocrystals; morphology control; oriented aggregation; platinum