title: Pd-M/C (M = Pd, Cu, Pt) Electrocatalysts for Oxygen Reduction Reaction in Alkaline Medium: Correlating the Electronic Structure with Activity.
abstract: The increasing global needs for clean and renewable energy have fostered the design of new and highly efficient materials for fuel cells applications. In this work, Pd-M (M = Pd, Cu, Pt) and Pt nanoparticles were prepared by a green synthesis method. The carbon-supported nanoparticles were evaluated as electrocatalysts for the oxygen reduction reaction (ORR) in alkaline medium. A comprehensive electronic and structural characterization of these materials was achieved using X-ray diffraction, high-resolution transmission electron microscopy, X-ray photoelectron spectroscopy, and X-ray absorption spectroscopy. Their electrochemical properties were investigated by cyclic voltammetry, while their activities for the ORR were characterized using steady-state polarization experiments. The results revealed that the bimetallic nanoparticles consist of highly crystalline nanoalloys with size around 5 nm, in which the charge transfer involving Pd and M atoms affects the activity of the electrocatalysts. Additionally, the samples with higher ORR activity are those whose d-band center is closer to the Fermi level.
authors.affiliation: Electron Spectroscopy Lab (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS) , Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS Brazil.
authors.forename: Marcus V
authors.initials: MV
authors.lastname: Castegnaro
authors.affiliation: Instituto de Química de São Carlos (USP) , 13560-970 São Carlos, SP Brazil.
authors.forename: Waldemir J
authors.initials: WJ
authors.lastname: Paschoalino
authors.affiliation: Instituto de Química de São Carlos (USP) , 13560-970 São Carlos, SP Brazil.
authors.forename: Mauro R
authors.initials: MR
authors.lastname: Fernandes
authors.affiliation: Institut für Anorganische und Analytische Chemie, Johannes Gutenberg-Universität , 55099 Mainz, Germany.
authors.forename: Benjamin
authors.initials: B
authors.lastname: Balke
authors.affiliation: Instituto de Química, Universidade Federal do Rio Grande do Sul (UFRGS) , Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS Brazil.
authors.forename: Maria C
authors.initials: MC
authors.lastname: M Alves
authors.affiliation: Instituto de Química de São Carlos (USP) , 13560-970 São Carlos, SP Brazil.
authors.forename: Edson A
authors.initials: EA
authors.lastname: Ticianelli
authors.affiliation: Electron Spectroscopy Lab (LEe-), Instituto de Física, Universidade Federal do Rio Grande do Sul (UFRGS) , Avenida Bento Gonçalves, 9500, 91501-970 Porto Alegre, RS Brazil.
authors.forename: Jonder
authors.identifier: 0000-0002-4143-1208
authors.initials: J
authors.lastname: Morais