Exploring the Why and How of Catalyst Morphology in CO₂ Reduction by Copper Oxide Using In Situ Analysis

Arrigo, Rosa

Abstract

Copper-based nanostructures are active catalysts for the electrochemical reduction of CO₂ (CO₂RR) to energy-rich products, with morphology often correlated to the catalytic performance. This study investigates the synthesis, structural evolution, and catalytic behaviour of Cu₂O nanoparticles (NPs), integrating morphological control with electronic structure analysis to reveal the true role of morphology in CO₂RR. At the university of Salford, we have developed a surfactant-free synthesis method, which produces Cu₂O NPs with tuneable shapes, including sharp-edged nanocubes (NCs) and novel popcorn-like morphologies (nano-popcorns, NPCs), under varying pH and atmospheric conditions. In-situ techniques, such as X-ray absorption fine structure (XAFS) and UV-Vis spectroscopy, capture the dynamic interplay of dissolution and condensation equilibria, shedding light on the evolving chemical speciation of Cu during nanoparticle formation.

In-situ electrochemical liquid scanning transmission electron microscopy (EC-LSTEM) at Freiburg University, in collaboration with the group of Anna Fischer, has revealed distinct dynamic behaviours of the particles under CO₂RR, depending on their starting morphology. Herein, I will establish parallels between the chemistry involved during synthesis as a function of macroscopic parameters, as revealed by in-situ and ex-situ XAFS and TEM analysis, and the behaviour of the particles under CO₂RR. By bridging these observations, I aim to explain how the particle morphology evolution during CO₂RR is linked to the electronic structure of the electrocatalysts, and how these changes explain catalytic selectivity and stability.

• Presentation Conference Type: Presentation / Talk
• Conference Name: MATSUS Spring 2025 Conference
• Start Date: Mar 3, 2025
• End Date: Mar 7, 2025
• Online Publication Date: Dec 16, 2024
• Publication Date: Dec 16, 2024
• Deposit Date: Apr 16, 2025
• Peer Reviewed: Peer Reviewed
• Book Title: Proceedings of the MATSUS Spring 2025 Conference
• DOI: https://doi.org/10.29363/nanoge.matsusspring.2025.450