KSEA events Operando X-ray absorption spectroscopy studies on CO electroreduction reaction (200124 KSEA Berkeley Chapter Seminar)
2020.01.30 12:59
TITLE: Operando X-ray absorption spectroscopy studies on CO
electroreduction reaction
SPEAKER: Dr. Soo Hong Lee
ABSTRACT: The rational design of high-performance electrocatalysts requires
a detailed understanding of structural features under realistic working
conditions. Oxide-derived Cu catalysts exhibit a remarkable selectivity towards
multi-carbon products for the electrochemical CO reduction reaction (CORR), but
the exact role of oxide remains elusive for explaining the performance
enhancements. Here, we used operando X-ray absorption spectroscopy coupled with
gas chromatography and electrochemical double-layer capacitance (EDLC)
measurements to show that the ethylene (C2H4) production is not correlated with
oxidation state or electrochemical surface area of the catalyst under high
current densities. In the gas-diffusion electrodes, the increased C2H4 activity
and selectivity were related to the morphological transformation that
originates from the in-situ electroreduction of the oxide structure at the
early stage of the reaction. These results give rise to an electrochemical
regeneration method that restores the original catalyst performances without
cell disassembly. Our study establishes a basis for the rational design of
highly active electrocatalysts for broad-range reactions in the gas-fed
device.
BIO: Dr. Soo Hong Lee is a PostDoc working with Dr. Walter S.
Drisdell in Joint center for artificial photosynthesis (JCAP), Chemical Science
Division of LBNL. He received Ph.D. and B.S. in Chemical engineering at Seoul
National University, South Korea. He is now working on operando X-ray studies
for CO2 and CO electroreduction reaction.
