TY - JOUR
T1 - Insights into the Low Overpotential Electroreduction of CO2 to CO on a Supported Gold Catalyst in an Alkaline Flow Electrolyzer
AU - Verma, Sumit
AU - Hamasaki, Yuki
AU - Kim, Chaerin
AU - Huang, Wenxin
AU - Lu, Shawn
AU - Jhong, Huei Ru Molly
AU - Gewirth, Andrew A.
AU - Fujigaya, Tsuyohiko
AU - Nakashima, Naotoshi
AU - Kenis, Paul J.A.
N1 - Funding Information:
The authors gratefully acknowledge financial support from the International Institute for Carbon Neutral Energy Research (WPI-I2CNER), sponsored by the Japanese Ministry of Education, Culture, Sports, Science and Technology, and from a Dow Chemical Company graduate fellowship to S.V. TGA was carried out in part in the Frederick Seitz Materials Research Laboratory Central Research Facilities, University of Illinois.
Publisher Copyright:
© 2017 American Chemical Society.
PY - 2018/1/12
Y1 - 2018/1/12
N2 - Cost competitive electroreduction of CO2 to CO requires electrochemical systems that exhibit partial current density (jCO) exceeding 150 mA cm-2 at cell overpotentials (|ηcell|) less than 1 V. However, achieving such benchmarks remains difficult. Here, we report the electroreduction of CO2 on a supported gold catalyst in an alkaline flow electrolyzer with performance levels close to the economic viability criteria. Onset of CO production occurred at cell and cathode overpotentials of just -0.25 and -0.02 V, respectively. High jCO (∼99, 158 mA cm-2) was obtained at low |ηcell| (∼0.70, 0.94 V) and high CO energetic efficiency (∼63.8, 49.4%). The performance was stable for at least 8 h. Additionally, the onset cathode potentials, kinetic isotope effect, and Tafel slopes indicate the low overpotential production of CO in alkaline media to be the result of a pH-independent rate-determining step (i.e., electron transfer) in contrast to a pH-dependent overall process.
AB - Cost competitive electroreduction of CO2 to CO requires electrochemical systems that exhibit partial current density (jCO) exceeding 150 mA cm-2 at cell overpotentials (|ηcell|) less than 1 V. However, achieving such benchmarks remains difficult. Here, we report the electroreduction of CO2 on a supported gold catalyst in an alkaline flow electrolyzer with performance levels close to the economic viability criteria. Onset of CO production occurred at cell and cathode overpotentials of just -0.25 and -0.02 V, respectively. High jCO (∼99, 158 mA cm-2) was obtained at low |ηcell| (∼0.70, 0.94 V) and high CO energetic efficiency (∼63.8, 49.4%). The performance was stable for at least 8 h. Additionally, the onset cathode potentials, kinetic isotope effect, and Tafel slopes indicate the low overpotential production of CO in alkaline media to be the result of a pH-independent rate-determining step (i.e., electron transfer) in contrast to a pH-dependent overall process.
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U2 - 10.1021/acsenergylett.7b01096
DO - 10.1021/acsenergylett.7b01096
M3 - Article
AN - SCOPUS:85040588296
SN - 2380-8195
VL - 3
SP - 193
EP - 198
JO - ACS Energy Letters
JF - ACS Energy Letters
IS - 1
ER -