Abstracts Book - IMRC 2018

• SF3-O060
CHARGE TRANSFER AND HYDROGEN ADSORPTION IN
PALLADIUM BASED BIMETALLIC NANO SYSTEMS: AN
EXPERIMENTAL AND THEORETICAL DFT STUDY
Carlos Quintanar 1 , Reyna Caballero 1 , Maira Ramos 1 , Elizabeth Chavira 2 , Magali Ugalde
Alcantara 2 , Hector Cruz Manjarres 3 , Francisco Espinosa Magaña 4
1 Universidad Nacional Autónoma de México, Física, F. Ciencias, Mexico. 2 Universidad Nacional
Autónoma de México, Instituto de Investigacion de Materiales, Mexico. 3 Universidad Nacional
Autónoma de México, Instituto de Fisica, Mexico. 4 Centro de Investigación en Materiales
Avanzados, S.C., Fisica de Materiales, Mexico.
Our work is aimed to understand the characteristics of non-ideal bi-metallic
systems, samples with porous and large surface areas. In doing this first, we
compared the charge transfer in the, palladium-silver, palladium-platinum
nano-surfaces.Then we focus in the silver-palladium nano system determining
the adsorption energies at several hydrogen adsorption sites, and also analyzing
the influence of hydrogen adsorption on the structure of the bimetallic nano
particle. For that, a variety of experimental methods including sputtering, solgel,
high resolution transmission electron microscopy and energy dispersive x-
ray spectrometry have been combined with density functional theory, for the
preparation, characterization and modelling of palladium, silver, platinum,
palladium-silver and palladium-platinum nano systems. This study explores the
connection between structure, electron density distribution, charge transfer,
and hydrogen adsorption on the bimetallic nano surface. We think that our
prepared samples might share more similarities with the industrial catalysts
than the model systems. Charge transfer was determined via density difference
analysis, and in addition, NBO and natural population analysis are also reported.
For the palladium silver system, our density difference analysis shows a large
charge transfer from the silver plane to the palladium plane and to the interface
between the planes.
Acknowledgment:
Financial support provided by UNAM-DGAPA-PAPIIT IN111816.
Keywords: Nano-catalysis, Palladium bimetallic, Nano-Clusters
Presenting authors email: carlos_quintanar@ciencias.unam.mx