I²CNER Webinar

International Institute for Carbon-Neutral Energy Research (I2CNER)
Moonshot for beyond Zero-Emission Society
Research Center for Negative Emissions Technologies
Kyushu University

Title

Understanding and Controlling
Electrochemistry for Electrolyzers and Batteries

SpeakerProf. Andrew A. Gewirth

Time&Date

Abstract

Department of Chemistry
University of Illinois at Urbana-Champaign
9:00 AM(JST), Wednesday, October 13th, 2021

This talk addresses the electrochemical reactivity associated with electrolyzers and batteries. Relevant toelectrolyzers we show that electrodeposition of CuAg or CuSn alloy films under suitable conditions yields
high surface area catalysts for the active and selective electroreduction of CO₂ to multi-carbonhydrocarbons and oxygenates. Alloy films containing Sn exhibit greater efficiency for CO production
relative to either Cu along or CuAg at low overpotentials. In-situ Raman and electroanalysis studies
suggest the origin of the high selectivity towards C₂ products to be a combined effect of the diminishedstabilization of the Cu₂O overlayer and the optimal availability of the CO intermediate due to the Ag or Sn
incorporated in the alloy. Sn-containing films exhibit less Cu₂O relative to either the Ag-containing or neatCu films, likely due to the increased oxophilicity of the admixed Sn. Incorporation of a polymer into the Cu
electrodeposit leads to very active CO₂ reduction electrocatalysis due to pH changes at the electrifiedinterface. Vibrational spectroscopy is used to evaluate the pH at the interface during electrolyzer
operation.
Relevant to batteries, we discuss solid electrolytes (SEs) which have become a practical option for lithium
ion and lithium metal batteries due to their improved safety over commercially available ionic liquids. The
most promising of the SEs are the thiophosphates whose excellent ionic conductivities at room
temperature approach those of commercially-utilized electrolytes. Hybrid solid-liquid electrolytes exhibit
higher ionic conductivities than their bare solid electrolyte counterparts due to decreased grain boundary
resistance, enhanced interfacial contact with electrodes, and decreased degradation at the interface.
Spectroscopic and structural studies on these latter materials lead to new formulations and artificial SEI
materials exhibiting advantageous properties.

About the SpeakerProfessor Andrew A. Gewirth received his A.B. from Princeton University in 1981 and his Ph.D. from Stanford
University in 1987. He joined the Illinois faculty in 1988 after postdoctoral work at the University of Texas, Austin.
A former Director of the School of Chemical Sciences at the University of Illinois, Professor Gewirth has received anumber of awards, among them a Presidential Young Investigator Award and the Department of Energy
Outstanding Accomplishment Award in Materials Chemistry.
Gewirth’s work addresses chemistry at interfaces, especially the solid-liquid interface in studies relevant to fuelcells, batteries, and other energy related devices. Gewirth uses advanced characterization techniques to examine
the mechanism of interfacial electrochemical reactions, and uses the resultant understanding to design newmaterials and catalysts. He has authored over 280 papers, delivered over 200 invited talks, organized several
conferences, chaired a US Department of Energy panel examining the future of electrical energy storage devices,and served as the University of Illinois lead for the Center for Electrical Energy Storage EFRC.

Registration

https://zoom.us/webinar/register/WN_HWuB5XC5QIKAgOjgtzYguw
HostProf. Miho Yamauchi

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