Electrochemical Oxidation of Ethanol on Polymer Electrolyte Fuel Cell. A Quantitative Study of the Reaction Pathways by On-line Mass Spectrometry

• Grant number: 12/17581-3
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: December 01, 2012
• End date: March 14, 2016
• Field of knowledge: Physical Sciences and Mathematics - Chemistry - Physical-Chemistry
• Principal Investigator: Fabio Henrique Barros de Lima
• Grantee: Adriana Coêlho Queiroz
• Host Institution: Instituto de Química de São Carlos (IQSC). Universidade de São Paulo (USP). São Carlos , SP, Brazil
• Associated research grant: 11/50727-9 - Development of systems for hydrogen production and for the generation and utilization of electrochemical energy, AP.TEM
• Associated scholarship(s): 14/02032-0 - Ethanol electro-oxidation in solid acid fuel cells: effect of the electrocatalyst and operation temperature on the reaction pathways, BE.EP.DR

Abstract

Ethanol is a promising candidate as fuel in polymer electrolyte fuel cells for application on portable electronic devices. In addition to the production and distribution network already existent in Brazil, the ethanol is a renewable fuel, which is important for the sustainability. Other advantage is its high energy content that corresponds to 12 electrons per ethanol molecule for its total oxidation to CO2. A high active electrocatalyst for the total ethanol electro-oxidation has to present a good performance for the steps C-H, C-C and O-H bond breaking, and C-O bond formation. Pt has presented the highest activity among the pure metals due to its better balance between the opposite trends of bond breaking and bond formation mentioned above, but its activity can be further increased by the modification of its electronic structure, and by the insertion of one or more metals that present higher activity for particular reaction steps. Nevertheless, little is know about the quantitative distribution of the reaction products, mainly for bi and trimetallic catalysts. Therefore, the aims of this project are related to the synthesis and characterization of bi and trimetallic nanostructured electrocatalysts formed by Pt in combination with Rh and with metal oxides, such as SnOx and PbOx. The quantitative conversion efficiency of ethanol to the different reaction products will be performed by on-line mass spectrometry using electrochemical half-cell and unit fuel cells with stagnant and flow electrolytes. The final objective is to elucidate the relation between the electrocatalyst composition and structure with the activity, efficiency and stability for the ethanol electro-oxidation. The results will be used as a base for the construction of passive direct ethanol fuel cell for the application on portable electronic devices.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SILVA, W. O.; QUEIROZ, A. C.; PAGANIN, V. A.; LIMA, F. H. B.. Faradaic efficiency of ethanol oxidation to CO2 at metallic nanoparticle/short-side-chain PFSA solid-state electrolyte interfaces investigated by on-line DEMS. JOURNAL OF ELECTROANALYTICAL CHEMISTRY, v. 824, p. 99-107, SEP 1 2018. (12/17581-3, 13/16930-7, 16/13323-0)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

QUEIROZ, Adriana Coêlho. Ethanol Electro-oxidation at Room and Intermediate Temperature: Quantitative Study of Reaction Vias by On-line Mass Spectrometry. 2016. Doctoral Thesis - Universidade de São Paulo (USP). Instituto de Química de São Carlos (IQSC/BT) São Carlos.