Effect of halide-modified model carbon supports on catalyst stability.
ACS Appl Mater Interfaces
; 4(12): 6728-34, 2012 Dec.
Article
em En
| MEDLINE
| ID: mdl-23194033
ABSTRACT
Modification of physiochemical and structural properties of carbon-based materials through targeted functionalization is a useful way to improve the properties and performance of such catalyst materials. This work explores the incorporation of dopants, including nitrogen, iodine, and fluorine, into the carbon structure of highly-oriented pyrolytic graphite (HOPG) and its potential benefits on the stability of PtRu catalyst nanoparticles. Evaluation of the changes in the catalyst nanoparticle coverage and size as a function of implantation parameters reveals that carbon supports functionalized with a combination of nitrogen and fluorine provide the most beneficial interactions, resulting in suppressed particle coarsening and dissolution. Benefits of a carefully tuned support system modified with fluorine and nitrogen surpass those obtained with nitrogen (no fluorine) modification. Ion implantation of iodine into HOPG results in a consistent amount of structural damage to the carbon matrix, regardless of dose. For this modification, improvements in stability are similar to nitrogen modification; however, the benefit is only observed at higher dose conditions. This indicates that a mechanism different than the one associated with nitrogen may be responsible for the improved durability.
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1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
ACS Appl Mater Interfaces
Ano de publicação:
2012
Tipo de documento:
Article