Under-cover stabilization and reactivity of a dense carbon monoxide layer on Pt(111)

A densely-packed CO overlayer on Pt(111) has been stabilised under a 2D cover formed by a  h-BN–graphene in-plane heterostructure. The 2D layer influences the CO–Pt bond and CO reacts with the h–BNG cover at an elevated temperature at the h-BN–graphene boundaries. 
 

Chem. Sci., 2019,10, http://dx.doi.org/10.1039/C8SC04461A
This article is Open Access.


It has been only recently recognized that hetereogeneous catalysis can take place in the confined space between catalyst surface and a weakly interacting 2D overlayer. Model studies under well-defined conditions are valuable for understanding the fundamental aspects of the new phenomena under 2D covers.
Although a few studies have been reported for molecule–catalyst interaction under graphene or hexagonal boron nitride (h-BN), no research in this new field has been reported for mixed 2D covers, such as in-plane h-BN–graphene (h-BNG) heterostructure presented in our work. In this work, we examine a model case of platinum catalyst in the form of plane Pt(111) single crystal covered by a hybrid h-BNG 2D layer and its interaction with carbon monoxide molecules.
Our experimental surface science approach yields intriguing discoveries and insights into the 2D cover–molecule–catalyst interactions. We show that it is possible to stabilize a densely-packed CO overlayer under the 2D cover, which allows using standard surface science techniques to characterize such structures normally unstable under ultra-high-vacuum conditions. Furthermore, we provide an experimental evidence of the influence of the 2D layer on the CO–Pt bond, but more importantly, we show that CO reacts with the h–BNG cover at an elevated temperature and the active sites are the h-BN–graphene boundaries. This reaction leads to some irreversible changes in the system. However, we also show a possible way how to recover this catalytic system.
 

This work was supported by the Italian MIUR through the national grant Futuro in ricerca 2012 RBFR128BEC ‘‘Beyond graphene: tailored C-layers for novel catalytic materials and green chemistry’’

 

EUROFEL project (RoadMap Esfri) and “Progetto Premiale 2012”–Project ABNANOTECH. 
The authors acknowledge the technical support of Federico Salvador and Paolo Bertoch.

Under-cover stabilization and reactivity of a dense carbon monoxide layer on Pt(111)

and  Federica Bondino** 
* pis@iom.cnr.it; **bondino@iom.cnr.it
 
The article was first published on 03 Dec 2018
Chemical Science, 2019, 10, 1857 - 1865

http://dx.doi.org/10.1039/C8SC04461A
This article is Open Access.
Ultima modifica il Giovedì, 14 Gennaio 2021 12:09