Rhodium effects on Pt anode materials in a direct alkaline ethanol fuel cell

Thamyres Fernandes Messa Moreira (1, 2) , Sidney Aquino Neto (2) , Charly Lemoine (1) , Boniface Kokoh (1) , Cláudia Morais (1) , Teko Napporn (1) , Paulo Olivi (2)

1 IC2MP [Poitiers] - Institut de chimie des milieux et matériaux de Poitiers [UMR 7285]
2 USP - Universidade de São Paulo = University of São Paulo

The development of efficient catalysts for ethanol oxidation in alkaline medium requires a synthetic approach that may prevent the surfactant molecules from being adsorbed at the catalytic sites and decreasing the electrochemical performance of the final direct ethanol fuel cell. To this goal, the recently reported surfactant-less Bromide Anion Exchange (BAE) method, appears as a promising route to conveniently aim at preparing PtRh alloys dispersed on carbon substrate. The catalysts prepared herein by the BAE method were characterized physicochemically to obtain structural information on the PtRh/C nanomaterials, their morphology (size and shape), and their chemical and surface composition. Electrochemical behavior and properties of these electrodes were then investigated in a halfcell before the implementation of a direct ethanol fuel cell (DEFC) in a home-made anion exchange membrane Teflon cell. The analysis of the electrolytic solution in the anodic compartment by chromatography revealed that acetate was the major reaction product and the carbonate amount increased with the Rh content in the bimetallic composition. With 2.8-3.6 nm particle sizes, the Pt50Rh50/C catalyst exhibited the highest activity towards the ethanol electrooxidation.

Mots clés: Rhodium; Direct Alkaline Ethanol Fuel cell; Platinum; Ethanol electrooxidation

Domaines: Catalyse; Autre

Thamyres Fernandes Messa Moreira, Sidney Aquino Neto, Charly Lemoine, Boniface Kokoh, Cláudia Morais, et al.. Rhodium effects on Pt anode materials in a direct alkaline ethanol fuel cell. RSC Advances, 2020, 10 (58), pp.35310-35317. ⟨10.1039/d0ra06570f⟩. ⟨hal-03054930⟩