Femtosecond Broad-Band Sum Frequency Generation Spectroscopy: Measurements of Ethanol Fuel Cell Catalysis
Abstract
This is a fundamental science project relevant to ethanol fuel cells (DEFCs). We studied ethanol electrooxidation (EOR) on polycrystaline platinum in acidic and alkaline media. The method used was the broadband sum-frequency generation (BB-SFG) spectroscopy that we connected to the solid/liquid interfacial research for the first time. In both alkaline and acidic media we monitored oxidation of isotopically labeled ethanol ((12)CH(3)-(13)CH(2)OH). Surface-adsorbed (12)CO and (13)CO were observed and showed different potential-dependent behaviors. The 12CO showed evidence of methyl-like species formation(-12CHx) that was difficult to oxidize to CO2; the 12CHx, was found not to be oixdatively removed until the electrode potential was swept past 0.65 V. In sulfuric acids the results included adsorbed acetate and co-adsorbed sulfuric acid anions. For the DEFC cathode, the Co-OEP macrocycle was chosen and characterized with both Raman and BBSFG spectroscopies. The emphasis was given to V11 transition at 1577 cm-1, as this band shifted in frequency as the transition metal center was changed. There is no Stark tuning effect associated with the Co-OEP macrocycle adsorption.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 03, 2012
- Accession Number
- ADA577485
Entities
People
- Andrzej Wieckowski
- Dana D. Dlott
Organizations
- University of Illinois Urbana–Champaign