The Catalytic Activity of Pt:Ru Nanoparticles for Ethylene Glycol and Ethanol Electrooxidation in a Direct Alcohol Fuel Cell

Author(s)

Silva, Julio Cesar M. ^[1] ; Ntais, Spyridon ^[2] ; Rajaraman, Vishwanathan ^[2] ; Teixeira-Neto, Erico ^[3] ; Teixeira-Neto, Angela A. ^[3] ; Neto, Almir O. ^[4] ; Antoniassi, Rodolfo M. ^[4] ; Spinace, Estevam V. ^[4] ; Baranova, Elena A. ^[2]

Affiliation

^[1] Univ Fed Fluminense, Inst Quim, Grp Eletroquim & Mat Nanoestruturados, Campus Valonguinho, BR-24020141 Niteroi, RJ - Brazil

^[2] Univ Ottawa, Dept Chem & Biol Engn, CCRI, 161 Louis Pasteur, Ottawa, ON K1N 6N5 - Canada

^[3] Brazilian Ctr Res Energy & Mat, Brazilian Nanotechnol Natl Lab, Rua Giuseppe Maximo Scolfaro 10-000, BR-13085903 Campinas, SP - Brazil

^[4] CNEN SP, IPEN, Ave Prof Lineu Prestes, 2242 Cidade Univ, BR-05508900 Sao Paulo, SP - Brazil

• Document type: Journal article
• Source: ELECTROCATALYSIS; v. 10, n. 3, p. 203-213, MAY 2019.
• Web of Science Citations: 0

Abstract

In this study, we investigated the carbon-supported PtRu nanoparticles with atomic ratios of Pt:Ru of 100:0, 90:10, 70:30, and 50:50 for ethanol and ethylene glycol electrooxidation in alkaline media. The nanoparticles were synthesized using sodium borohydride method with 20wt% of metals loading on carbon. The nanoparticle mean sizes were 7.3nm, 5.7nm, 5.2nm, and 5.1nm for Pt/C, Pt90Ru10/C, Pt70Ru30/C, and Pt50Ru50/C, respectively. X-ray diffraction (XRD) analysis revealed that Pt and PtRu electrocatalysts have face-centered cubic (fcc) structure and suggests the alloy formation for all PtRu/C materials, which was further supported by the X-ray photoelectron spectroscopy (XPS). Based on XPS analysis, Pt50Ru50/C has higher amount of Pt oxides on the surface than Pt70Ru30/C. Electrochemical results demonstrated that the addition of Ru to Pt enhances the catalytic activity towards ethanol and ethylene glycol electrooxidadion. The catalyst of Pt50Ru50/C composition showed the lowest onset potential for ethanol and ethylene glycol electrooxidation, which were 160 and 70mV lower than for Pt/C, respectively. Furthermore, this catalyst outperformed Pt/C and other PtRu/C compositions in chronoamperometric and direct alcohol fuel cell (DAFC) experiments. DAFC experiments using Pt50Ru50/C as anode had the power density 40 and 14% higher than using Pt/C for ethanol and ethylene glycol, respectively. The promotion is due to the bi-functional mechanism and/or electronic effect of two metals in the alloy. (AU)

• FAPESP's process: 14/09087-4 - Studies on the use of bioethanol in proton exchange membrane and solid oxide fuel cells
• Grantee: Marcelo Linardi
• Support Opportunities: Research Projects - Thematic Grants
• FAPESP's process: 14/09868-6 - Ammonia oxidation reaction and products determination using electrocatalysts and supports with enhanced durability and high catalytic activity
• Grantee: Júlio César Martins da Silva
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor