TY - JOUR
T1 - Investigation of the ethanol electrooxidation in alkaline membrane electrode assembly by differential electrochemical mass spectrometry
AU - Rao, V.
AU - Hariyanto,
AU - Cremers, C.
AU - Stimming, U.
PY - 2007/10
Y1 - 2007/10
N2 - The fuel cell differential electrochemical mass spectrometry (FC-DEMS) measurements were performed for studying the ethanol dxidation reaction (EOR), using alkaline membrane electrode assemblies (MEAs) made up of nanoparticle Pt catalyst and alkaline polymeric membranes. The obtained results indicate that in an alkaline medium, ethanol undergoes significantly more complete electro-oxidation to CO2 than in an acidic MEA using the same Pt anode. The CO2 current efficiency (CCE) can be compared for acidic and alkaline MEA with similar electrochemical active area on the anode side. The CCE estimated, in case of alkaline MEA, with Pt anode, is around 55% at 0.8 V/RHE, 60 °C and 0.1 M ethanol. In comparison, under similar conditions, acidic MEAs using the same anode catalyst show only 2% CCE. This might indicate that the C-C bond scission rates are much higher in alkaline media. However, the mechanismof ethanol oxidation in alkaline media is not exactly known. CO 2 produced in electrochemical reaction forms soluble carbonates in the presence of aqueous alkaline electrolyte. This makes it difficult to study ethanol oxidation in alkaline media using FTIR or model DEMS systems. The alkaline polymer electrolyte membranes as used in this study for making alkaline MEAs provide an important opportunity to observe CO2 produced during EOR using FC-DEMS system.
AB - The fuel cell differential electrochemical mass spectrometry (FC-DEMS) measurements were performed for studying the ethanol dxidation reaction (EOR), using alkaline membrane electrode assemblies (MEAs) made up of nanoparticle Pt catalyst and alkaline polymeric membranes. The obtained results indicate that in an alkaline medium, ethanol undergoes significantly more complete electro-oxidation to CO2 than in an acidic MEA using the same Pt anode. The CO2 current efficiency (CCE) can be compared for acidic and alkaline MEA with similar electrochemical active area on the anode side. The CCE estimated, in case of alkaline MEA, with Pt anode, is around 55% at 0.8 V/RHE, 60 °C and 0.1 M ethanol. In comparison, under similar conditions, acidic MEAs using the same anode catalyst show only 2% CCE. This might indicate that the C-C bond scission rates are much higher in alkaline media. However, the mechanismof ethanol oxidation in alkaline media is not exactly known. CO 2 produced in electrochemical reaction forms soluble carbonates in the presence of aqueous alkaline electrolyte. This makes it difficult to study ethanol oxidation in alkaline media using FTIR or model DEMS systems. The alkaline polymer electrolyte membranes as used in this study for making alkaline MEAs provide an important opportunity to observe CO2 produced during EOR using FC-DEMS system.
KW - Alkaline Anion Exchange Membranes (AAEM)
KW - CO Current Efficiency (CCE)
KW - Direct Ethanol Fuel Cell (DEFC)
KW - Electrocatalysis
KW - Ethanol electro-oxidation
KW - Fuel cell
KW - Fuel cell differential electrochemical mass spectrometry (FC-DEMS)
UR - http://www.scopus.com/inward/record.url?scp=35948971712&partnerID=8YFLogxK
U2 - 10.1002/fuce.200700026
DO - 10.1002/fuce.200700026
M3 - Article
AN - SCOPUS:35948971712
SN - 1615-6846
VL - 7
SP - 417
EP - 423
JO - Fuel Cells
JF - Fuel Cells
IS - 5
ER -