Synthesis and Structural Evolution of Nickel-Cobalt Nanoparticles Under H2 and CO2.
Small
; 11(25): 3045-53, 2015 Jul 01.
Article
em En
| MEDLINE
| ID: mdl-25727527
ABSTRACT
Bimetallic nanoparticle (NP) catalysts are interesting for the development of selective catalysts in reactions such as the reduction of CO2 by H2 to form hydrocarbons. Here the synthesis of Ni-Co NPs is studied, and the morphological and structural changes resulting from their activation (via oxidation/reduction cycles), and from their operation under reaction conditions, are presented. Using ambient-pressure X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, and transmission electron microscopy, it is found that the initial core-shell structure evolves to form a surface alloy due to nickel migration from the core. Interestingly, the core consists of a Ni-rich single crystal and a void with sharp interfaces. Residual phosphorous species, coming from the ligands used for synthesis, are found initially concentrated in the NP core, which later diffuse to the surface.
Texto completo:
1
Base de dados:
MEDLINE
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article