Abstracts Book - IMRC 2018

• SF5-P075
EFFECT OF DOUBLE-LAYER STRUCTURE ON THE MULTI-STEP
ELECTRON-TRANSFER KINETICS OF CO2 ELECTROCHEMICAL
REDUCTION AT SEMICONDUCTOR CATHODES BEARING Ag, Cu,
AND BIMETALLIC Ag/Cu NANOPARTICULATE ARRAYS
ELECTRODEPOSITED BY POTENTIOSTATIC DOUBLE-PULSE
TECHNIQUE.
Juan Manriquez 1 , Jorge Alberto Banda Alemán 1 , German Orozco 1 , Erika Bustos 1 , Selene
Sepulveda 2
1 Centro de Investigación y Desarrollo Tecnológico en Electroquímica, Department of Science,
Mexico. 2 Universidad Autónoma de Nuevo León, Centro de Innovación, Investigación y
Desarrollo en Ingeniería y Tecnología, Mexico.
In-doped SnO 2 (ITO) cathodes bearing Ag, Cu and bimetallic Ag/Cu
nanoparticulate arrays (cathode systems ITO//Ag, ITO//Cu and ITO//Ag/Cu,
respectively) were prepared by potentiostatic double-pulse technique and
employed for studying the multi-step charge-transfer kinetics of the
CO 2 electrochemical reduction (CO 2 ER) in propylene carbonate solution. Our
results demonstrated, on one hand, that the current exchange density of
the rds for the CO 2 electrochemical reduction (i o,rds ) predominantly depends on
the values achieved by the outer-Helmholtz plane (OHP) potential (ΔΨ OHP,rds ) at
the three cathode systems here explored.Furthermore, these results showed
that a large ΔΨ OHP,rds (-647 mV) promoted a small i o,rds (7.95×10 -8 A·cm -2 ) for the
CO 2 reduction at the cathode system ITO//Cu, whereas a small ΔΨ OHP,rds (-168
mV) produced a large i o,rds (1.64×10 -6 A·cm -2 ) for the CO 2 reduction at the
cathode system ITO//Ag. On the contrast, intermedium values
of ΔΨ OHP,rds and i o,rds (-333 mV, 2.39×10 -7 A·cm -2 ) were found for the
CO 2 reduction at the cathode system ITO//Ag/Cu, thus demonstrating that the
individual electrocatalytic properties of Ag and Cu can be coupled in a bimetallic
array to intentionally tune the CO 2 ER rate in nonaqueous solvents having low
proton avalability.
Acknowledgment:
The authors thank the Mexican Council for Science and Technology (CONACyT)
for its financial support of this work (grant 258789). J.A.B.A. acknowledge
CONACyT for his PhD scholarship (grant 405801).