Electroreduction of CO 2 on LaBaCoO Perovskites

J.F ZAPATA; VIVA F. A.; BARRAL M. A.; VILDOSOLA V.

Cartagena

Otro; ICTP Caribbean School on Materials for Clean Energy; 2019

ICTP - International Centre for Theoretical Physics

The electrochemical reduction of carbon dioxide (CO2) has attracted the interest of the scientific community for decades, since it can facilitate the sustainable low-temperature redox cycle for energy storage and conversion [1]. The electroreduction of CO2 to hydrocarbons (such as Methane) on Cu electrodes has attained remarkable attention since its discovery [2]. However, the dearth of materials able to catalyze the reaction of CO2 to Methane and its high inefficient overpotential makes necessary to expand the search for new catalysts. Previous studies of the reactivity and catalytic capacity of cobalt-based perovskites have shown their high affinity for the absorption and conversion of CO2 [3]. In this work, we focus on a new cobalt-based perovskite, LaBaCoO, and perform a cyclic voltammetry experiment. We use a conventional three-electrode cell and potassium bicarbonate (KHCO3) as electrolyte, saturated with N2 and CO2. The analysis of the I vs V curves shows the existence of additional reduction processes when there is a high concentration of CO2 in the electrolyte that do not happens in a solution rich in N2, providing evidence of CO2 electrochemical reduction in the LaBaCoO perovskite. Additionally, as a first step to describe theoretically the capability of this perovskite to reduce CO2, we present complementary ab-initio calculations based on the density functional theory. In particular, we study the absorption process of CO in different facets of the LaBaCoO surface that was proven to be a crucial intermediate in the CO2 reduction in transition-metal electrodes [4].Bibliography [1] Viva, F. A., Advanced Chemistry Letters, 1(3), 2013. [2] 1] Kortlever, R ; Shen, J ; Klaas Jan , P ; Calle-Vallejo, F ; Koper, M. T. ; (2015), J. Phys. Chem. Lett., vol 6 (20), pp 4073?4082.[3] Hwang J., Rao R., Katayama Y., J, Phys. Chem., 122 (2018), 20391-20401.[4] Andrew A. Peterson., Jens K. Norskov., J, Phys. Chem. Lett., 3 (2012), 251-258.