Carbon supported PtNiCu nanostructured particles for the electro-oxidation of ethanol in acid environment

ALVAREZ, ANDREA E.; SIEBEN, JUAN MANUEL; DUARTE, MARTA M.E.; CASTAGNA, RODRIGO M.; SANCHEZ, MIGUEL D.

Materials Today Energy

Elsevier

Lugar: Amsterdam; Año: 2020 vol. 15

2468-6069

Four carbon supported trimetallic PtNiCu nanostructured catalysts have been successfully synthesized by a two-step chemical/electrochemical reduction route. Nanoparticles with average sizes in the range of 2.2-3.5 nm with mixed alloy, pseudo core-shell and core-shell patterns were obtained. All as-prepared electrocatalysts exhibited high electroactive surface areas, ranging from 93 to 117 m2g-1. The electro-catalytic activity of the trimetallic materials towards the ethanol oxidation reaction (EOR) was studied by cyclic voltammetry and chronoamperometry at temperatures between 20 and 60 ºC. Among the studied catalysts, the alloy nanomaterial with a Pt:Cu:Ni surface atomic ratio of 36.8:57.0:6.2 and the pseudo core-shell material with a Pt:Cu:Ni surface atomic ratio of 18.0:43.6:38.4 exhibited the best performance for the EOR. These nanostructured catalysts presented lower onset potentials, four times higher mass activities, and 8e10 times higher specific activities than a commercial PtRu/C catalyst. The kinetic parameters (i.e., Tafel slope and apparent activation energy) indicated that the electro-oxidation of ethanol on the as-prepared catalysts was faster than on PtRu/C