Title
On the promotional effect of Cu on Pt for hydrazine electrooxidation in alkaline medium
Date Issued
15 November 2018
Access level
metadata only access
Resource Type
journal article
Author(s)
Crisafulli R.
de Barros V.
Rodrigues de Oliveira F.
de Araújo Rocha T.
Zignani S.
Spadaro L.
Palella A.
Dias J.
Universidade de Brasília
Publisher(s)
Elsevier B.V.
Abstract
Pt/C and PtCu/C electrocatalysts with nominal Pt:Cu atomic ratios of 75:25, 50:50, and 25:75 were prepared using N2H4 as reducing agent and carbon black Vulcan XC-72R as support. The obtained materials were physically characterized by X-ray diffraction, Energy-Dispersive X-ray analysis, Transmission Electron Microscopy images, X-ray Photoelectron Spectroscopy (XPS), and Temperature-Programmed Reduction analysis. Cyclic voltammetry, linear sweep voltammetry, and chronoamperometry (TPR) measurements were carried out in a three-electrode glass cell to evaluate the electrochemical activity towards hydrazine electrooxidation in alkaline medium along with single-cell direct hydrazine fuel cell (DHFC) tests. The actual composition of the electrocatalysts evidenced a slightly lower Cu fraction compared to the nominal one. The X-ray diffractograms of the electrocatalysts showed the typical face-centered cubic structure of Pt alloys, with the highest fraction of Cu alloyed to Pt being achieved with the almost equiatomic catalyst. An important fraction of the remaining non-alloyed Cu is in the form of a copper oxide, as evidenced by XPS and TPR measurements. The electrochemical tests evidenced that the coexistence of part of the Cu alloyed with Pt and copper oxide achieved in the PtCu/C electrocatalysts enhances the performance compared to Pt/C. In particular, the optimum formulation is attained by the Pt53Cu47/C electrocatalyst, allowing maximization of the electrocatalytic activity towards hydrazine electrooxidation and the single-cell performance at 60 and 80 °C.
Start page
36
End page
44
Volume
236
Language
English
OCDE Knowledge area
Ingeniería química
Scopus EID
2-s2.0-85046755159
Source
Applied Catalysis B: Environmental
ISSN of the container
09263373
Source funding
Dermatology Foundation
Sponsor(s)
The authors thank Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for a scholarship awarded to Rudy Crisafulli. In addition, we acknowledge the research scholarship provided by CNPq and financial support provided by UnB/DPI/IQ , MCTI/CNPq , CAPES , FAP-DF , and FINEP/CTPetro . The authors thank Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for a scholarship awarded to Rudy Crisafulli. In addition, we acknowledge the research scholarship provided by CNPq and financial support provided by UnB/DPI/IQ, MCTI/CNPq, CAPES, FAP-DF, and FINEP/CTPetro.
Sources of information: Directorio de Producción Científica Scopus