Electrochemical study of PtRh/C and PtRhNi/C electrocatalysts for ethylene glycol oxidation
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In the last decades, the ethylene glycol has been considered as another option of fuel, in both acid and alkaline solutions, for fuel cells application. Pt-based electrocatalysts are used in this type of technology but it is necessary to add a second or third oxophilic metal to form bimetallic or trimetallic alloys. Alloys with a second or a third metal modify electrocatalytic properties of Pt in order to overcome poisoning effects and enhancement of the electrocatalytic activity of platinum-based electrocatalyst. PtRh/C and PtRhNi/C electrocatalysts were prepared by alcohol reduction method, and their catalytic activity and stability were evaluated by cyclic voltammetry and chronoamperometry, in alkaline medium using a KOH solution with ethylene glycol in concentrations of 0.5 and 1.0 mol L−1. The results showed that the binary electrocatalyst has a higher electrocatalytic performance and obtain about 90% more energy density than PtRhNi/C. This result indicates that the higher amount of Rh in the alloy presents a synergistic effect with Pt. Chronoamperometry tests show that both electrocatalysts have an active surface and tolerance to poisoning by intermediate products, and the presence of Ni in the ternary electrocatalyst contributes to raise this tolerance.
The authors thank CNPq (Grants # 554613/2010-7 and # 456336/2013-3), FAPEAM, IFAM, and CAPES for funding this study.
- 1.González-Quijano D, Pech-Rodríguez WJ, Escalante-García JI, Vargas-Gutiérrez G, Rodríguez-Varela FJ (2015) Electrocatalysts for ethanol and ethylene glycol oxidation reactions. Part II: effects of the polyol synthesis conditions on the characteristics and catalytic activity of Pt-Ru/C anodes. Int J Hydrog Energy 40(48):17291–17299. https://doi.org/10.1016/j.ijhydene.2015.06.154 CrossRefGoogle Scholar
- 3.Fashedemi OO, Miller HA, Marchionni A, Vizza F, Ozoemena KI (2015) Electro-oxidation of ethylene glycol and glycerol at palladium-decorated FeCo@Fe core–shell nanocatalysts for alkaline direct alcohol fuel cells: functionalized MWCNT supports and impact on product selectivity. J Mater Chem A3:7145–7156CrossRefGoogle Scholar
- 15.Delpeuch B, Maillard A, Chatenet F, Soudant P, Cremers C (2016) Ethanol oxidation reaction (EOR) investigation on Pt/C, Rh/C, and Pt-based bi- and tri-metallic electrocatalysts: a DEMS and in situ FTIR study. Appl Catal B Environ 181:672–680. https://doi.org/10.1016/j.apcatb.2015.08.041 CrossRefGoogle Scholar
- 20.Silva EL, Correa OS, Oliveira EL, Takimi AS, Radtke C, Malfatti CF (2010) Síntese e caracterização de ligas de Pt-Sn-Ni para aplicação como catalisadores em células a combustível do tipo DEFC. CBECiMat 19:21–25Google Scholar