Protecting Ceria Nanocatalysts-The Role of Sacrificial Barriers.
ACS Appl Mater Interfaces
; 10(38): 32510-32515, 2018 Sep 26.
Article
in En
| MEDLINE
| ID: mdl-30160106
ABSTRACT
Forces acting on a functional nanomaterial during operation can cause plastic deformation and extinguish desirable catalytic activities. Here, we show that sacrificial materials, introduced into the catalytic composite device, can absorb some of the imposed stress and protect the structural integrity and hence the activity of the functional component. Specifically, we use molecular dynamics to simulate uniaxial stress on a ceria (CeO2) nanocube, an important functional material with respect to oxidative catalysis, such as the conversion of CO to CO2. We predict that the nanocube, protected by a "soft" BaO or "hard" MgO sacrificial barrier, is able to withstand 40.1 or 26.5 GPa, respectively, before plastic deformation destroys the structure irreversibly; the sacrificial materials, BaO and MgO, capture 71 and 54% of the stress, respectively. In comparison, the unprotected nanoceria catalyst deforms plastically at only 2.5 GPa. Furthermore, modeling reveals the deformation mechanisms and the importance of microstructural features, insights that are difficult to measure experimentally.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Type of study:
Prognostic_studies
Language:
En
Journal:
ACS Appl Mater Interfaces
Journal subject:
BIOTECNOLOGIA
/
ENGENHARIA BIOMEDICA
Year:
2018
Document type:
Article
Affiliation country:
Reino Unido