1 research outputs found
The Role of Bismuth in Suppressing the CO Poisoning in Alkaline Methanol Electrooxidation: Switching the Reaction from the CO to Formate Pathway
While
tuning the electronic structure of Pt can thermodynamically
alleviate CO poisoning in direct methanol fuel cells, the impact of
interactions between intermediates on the reaction pathway is seldom
studied. Herein, we contrive a PtBi model catalyst and realize a complete
inhibition of the CO pathway and concurrent enhancement of the formate
pathway in the alkaline methanol electrooxidation. The key role of
Bi is enriching OH adsorbates (OHad) on the catalyst surface.
The competitive adsorption of CO adsorbates (COad) and
OHad at Pt sites, complementing the thermodynamic contribution
from alloying Bi with Pt, switches the intermediate from COad to formate that circumvents CO poisoning. Hence, 8% Bi brings an
approximately 6-fold increase in activity compared to pure Pt nanoparticles.
This notion can be generalized to modify commercially available Pt/C
catalysts by a microwave-assisted method, offering opportunities for
the design and practical production of CO-tolerance electrocatalysts
in an industrial setting