Pt(3)SnNi/C nanoparticle electrocatalysts for the ethanoi oxidation reaction: Ni stability study

• Published in: Electrochimica acta Vol. 96; pp. 243 - 252
• Main Authors: Parreira, Luanna Silveira, Da Silva, Julio Cesar Martins, D'Villa-Silva, Melina, Simoes, Fernando Carmona, Garcia, Samara, Gaubeur, Ivanise, Aurelio, Marco, Cordeiro, Liutheviciene, Leite, Edson Roberto, Dos Santos, Mauro Coelho
• Format: Journal Article
• Language: English
• Published: 30.04.2013
• Subjects: Accelerated tests; Electrocatalysts; Nanocomposites; Nanomaterials; Nanostructure; Nickel; Oxidation; Platinum
• ISSN: 0013-4686

This work describes the use of Pt(3)Sn/C, Pt(3)Ni/C and Pt(3)SnNi/C nanoparticle electrocatalysts with a 20% metal loading on carbon prepared using the polymeric precursor method for the ethanoi oxidation reaction (EOR). XRD measurements revealed the presence of segregated Pt and NiO phases in the PtiNi/C electrocatalysts, whereas for PtiSnNi/C. there was some evidence that Ni and Sn atoms are incorporated into the Pt structure with the presence of segregated SnO(2) and NiO phases. The mean crystallite sizes were 3.6, 5.7 and 7.2 nm for Pt(3)Sn/C, Pt(3)Ni/C, and Pt(3)SnNi/C, respectively. The onset oxidation potential obtained for the EOR using Pt(3)SnNi/C was close to 0.22 V. Chronoamperometric measurements revealed that the highest current densities for the EOR were obtained using the Pt(3)SnNi/C nanoparticle electrocatalysts (16 mAmg(pt)(-1)). Based on the Ni accelerated stress tests, this element was more stable in the ternary material. In contrast, there was a change in the product formation pathways before (acetalde-hyde and acetic acid were the primary products) and after the accelerated stress tests (acetaldehyde was the primary product) for the Pt(3)SnNi/C catalyst. The experimental results indicate that the Pt(3)SnNi/C electrocatalysts exhibited better electrocatalytic activity compared to the other electrocatalysts for the EOR. It is suggested that this activity is related to the presence of Ni, which can modify the electronic structure of Pt and combine with Sn to facilitate the removal of adsorbed CO on the surface of the Pt, thereby promoting the EOR.