title: Evolution of the PVP-Pd Surface Interaction in Nanoparticles through the Case Study of Formic Acid Decomposition.
abstract: Palladium nanoparticles (Pd NPs) were synthesized by the reduction-by-solvent method using polyvinylpirrolidone (PVP) as capping agent. The nonstatic interaction between PVP and the metallic surface may change the properties of the NPs due to the different possible interactions, through either the O or N atoms of the PVP. In order to analyze these effects and their repercussions in their catalytic performance, Pd NPs with various PVP/Pd molar ratios (1, 10, and 20) were prepared, deposited on silica, and tested in the formic acid decomposition reaction. The catalytic tests were conducted using catalysts prepared by loading NPs with three different time lapses between their purification and their deposition on the silica support (1 day, 1 month, and 6 months). CO adsorption, FTIR spectroscopy, XPS, and TEM characterization were used to determine the accessibility of the Pd NPs surface sites, the electronic state of Pd, and the average NPs size, respectively. The H2production from the formic acid decomposition reaction has a strong dependence on the Pd surface features, which in turn are related to the NPs aging time due to the progressive removal of the PVP.
authors: Materials Science Institute and Inorganic Chemistry Department, Alicante University , Ap. 99, E-03080 Alicante, Spain.
authors: Jaime
authors: J
authors: García-Aguilar
authors: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamada-oka, Suita, Japan.
authors: Miriam
authors: M
authors: Navlani-García
authors: Materials Science Institute and Inorganic Chemistry Department, Alicante University , Ap. 99, E-03080 Alicante, Spain.
authors: Ángel
authors: Á
authors: Berenguer-Murcia
authors: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamada-oka, Suita, Japan.
authors: Kohsuke
authors: K
authors: Mori
authors: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamada-oka, Suita, Japan.
authors: Yasutaka
authors: Y
authors: Kuwahara
authors: Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University , 2-1 Yamada-oka, Suita, Japan.
authors: Hiromi
authors: H
authors: Yamashita
authors: Materials Science Institute and Inorganic Chemistry Department, Alicante University , Ap. 99, E-03080 Alicante, Spain.
authors: Diego
authors: D
authors: Cazorla-Amorós