(212d) Understanding the Electrodeposition Mechanism of Chiral Cu Catalyst for the Efficient Electrochemical Carbon Dioxide Reduction

In the past years, the concept of chirality-induced spin selectivity (CISS) has been shown to improve the efficiency of oxygen evolution reactions by stabilizing only one spin state of charge carriers at the catalyst surface leading to a reduction in the efficiency of peroxide and singlet oxygen formation vs triplet oxygen formation. However, the detailed role of chiral organic molecules during the electrodeposition of metal/metal oxide electrocatalysts have not been investigated. In this work, we develop in situ spec-echem techniques to understand the in-depth mechanism of the enantiospecific electrodeposition and demonstrate how the CISS phenomenon can be used to control the reactivity and selectivity at the cathodic side by employing chiral Cu-based electrocatalysts. The onset potential of HER on chiral Cu catalysts negatively shifts compared to the achiral counterpart despite very similar physical and chemical properties of catalyst films. The electrochemical impedance spectroscopy suggests an altered reaction pathway and more sluggish HER kinetics on chiral Cu catalysts, leading to high Faradaic efficiency and selectivity of desired carbon products. Our findings provide insight into the potential of chiral catalysts for controlling the selectivity during CO2R and other valuable reduction reactions.