Addition of CeO2 Nanorods in PtSn-Based Electrocatalysts for Ethanol Electrochemical Oxidation in Acid Medium

This work describes the preparation of Pt/C, PtxSny/C and PtxSny(CeO2 nanorods/C) nanoparticle catalysts synthesized by the chemical reduction method via sodium borohydride for the ethanol oxidation reaction. Using X-ray diffractogram analysis, it was verified that no alloy formation occurred between platinum (Pt) and tin (Sn). The distribution of the nanoparticles in the support occurs in a more agglomerated form for the materials containing Sn and CeO2 nanorods (NR). The electrocatalyst Pt3Sn1_20%NRCeO2/C was highlighted in CO-stripping experiments because it showed the lowest onset potential for CO oxidation and the highest value for the electrochemically active surface area. The other electrochemical experiments for ethanol oxidation showed similar activities for the Pt3Sn1/C and Pt3Sn1_20%NRCeO2/C electrocatalysts. The observed effect can be associated with defects in the structure of the CeO2 nanorods, the electrochemical active surface area, and the properties of the CeO2 nanorods related to enhancing the generation of oxy-hydroxy species at lower potentials compared to PtSn/C electrocatalysts, which increased the CO oxidation as measured using stripping experiments. For this reason, it is possible to both use less platinum and to obtain behavior close to that of PtSn/C electrocatalysts for ethanol oxidation reaction (EOR).