Atomic Structure Evolution of Pt-Co Binary Catalysts Single Metal Sites versus Intermetallic Nanocrystals

Atomic Structure Evolution of Pt-Co Binary Catalysts : Single Metal Sites versus Intermetallic Nanocrystals

© 2021 Wiley-VCH GmbH.

Bibliographische Detailangaben
Veröffentlicht in:Advanced materials (Deerfield Beach, Fla.). - 1998. - 33(2021), 48 vom: 01. Dez., Seite e2106371
1. Verfasser: Li, Xing (VerfasserIn)
Weitere Verfasser: He, Yanghua, Cheng, Shaobo, Li, Boyang, Zeng, Yachao, Xie, Zhenhua, Meng, Qingping, Ma, Lu, Kisslinger, Kim, Tong, Xiao, Hwang, Sooyeon, Yao, Siyu, Li, Chenzhao, Qiao, Zhi, Shan, Chongxin, Zhu, Yimei, Xie, Jian, Wang, Guofeng, Wu, Gang, Su, Dong
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 2021
Zugriff auf das übergeordnete Werk:Advanced materials (Deerfield Beach, Fla.)
Schlagworte:Journal Article electrocatalysts fuel cells ordered Pt intermetallics oxygen reduction single Pt sites
Beschreibung
Zusammenfassung:© 2021 Wiley-VCH GmbH.
Due to their exceptional catalytic properties for the oxygen reduction reaction (ORR) and other crucial electrochemical reactions, PtCo intermetallic nanoparticle (NP) and single atomic (SA) Pt metal site catalysts have received considerable attention. However, their formation mechanisms at the atomic level during high-temperature annealing processes remain elusive. Here, the thermally driven structure evolution of Pt-Co binary catalyst systems is investigated using advanced in situ electron microscopy, including PtCo intermetallic alloys and single Pt/Co metal sites. The pre-doping of CoN4 sites in carbon supports and the initial Pt NP sizes play essential roles in forming either Pt3 Co intermetallics or single Pt/Co metal sites. Importantly, the initial Pt NP loadings against the carbon support are critical to whether alloying to L12 -ordered Pt3 Co NPs or atomizing to SA Pt sites at high temperatures. High Pt NP loadings (e.g., 20%) tend to lead to the formation of highly ordered Pt3 Co intermetallic NPs with excellent activity and enhanced stability toward the ORR. In contrast, at a relatively low Pt loading (<6 wt%), the formation of single Pt sites in the form of PtC3 N is thermodynamically favorable, in which a synergy between the PtC3 N and the CoN4 sites could enhance the catalytic activity for the ORR, but showing insufficient stability
Beschreibung:Date Revised 01.12.2021
published: Print-Electronic
Citation Status PubMed-not-MEDLINE
ISSN:1521-4095
DOI:10.1002/adma.202106371