Efficient electrooxidation of ethanol on Bi@Pt/C nanoparticles: (i) Effect of monolayer Bi deposition on specific sites of Pt nanoparticle (ii) Calculation of average number of e(-)s without help of chemical analysis

摘要

Influence of Bi adatoms on the electrochemical activity of Pt for ethanol oxidation in alkaline medium was studied by varying the Bi coverage from a full monolayer to partial monolayer on Pt nanoparticles. The core(Pt)@shell(Bi)/C nanoparticles were synthesized in bulk with a full monolayer of Bi shell followed by etching of surface Bi atoms from the specific sites to obtain partial monolayer. Both the electrochemical and the STEM characterizations confirmed the core@shell structure of Bi@Pt nanoparticles. It was observed that the presence of Bi as partial or full monolayer increased the electrochemical activity of Pt for ethanol oxidation by 3-4.5 times in alkaline medium. In addition, the average number of electrons transferred during the oxidation reaction and rate constants were evaluated from chronocoulometry data obtained for ethanol electrooxidation. (C) 2017 Elsevier Ltd. All rights reserved.