NSF-DFG MISSION: Comprehensive Operando Analysis of Electrolyte-Solid Interface Dynamics for Enhanced Electrocatalytic CO2 Conversion

Global initiatives aim to significantly reduce carbon dioxide (CO2) emissions by 2030 and achieve net-zero emissions by 2050. Electrocatalytic CO2 reduction (e-CO2RR) has emerged as a promising approach to convert CO2 into valuable chemicals and fuels using renewable electricity. However, current e-CO2RR systems face efficiency and stability limitations that hinder their practical implementation. Copper-based catalysts, while selective towards hydrocarbon production, suffer from performance degradation over extended operation. Leveraging a collaboration between Northwestern University in the US and the Fritz Haber Institute of the Max Planck Society in Germany, this project focuses on developing techniques for studying novel catalysts under realistic operating conditions and integrating advanced synthesis, characterization, and modeling methods to unravel the dynamic changes during reaction. Fundamental understandings gained from this project will provide essential guidance for developing catalysts that can be scaled up for real-world applications and enabling large-scale CO2 utilization for chemical manufacturing and carbon management. Beyond the technical aspects, the investigators are deeply invested in educational and outreach initiatives ranging from elementary school children to post-doctoral researchers. Those efforts will continue under the project, with specific efforts focused on training graduate students in the most advanced microscopy techniques relevant to catalyst design and performance under realistic electrochemical reaction conditions. The scientific underpinning of this project is to elucidate the dynamics occurring at the catalyst-electrolyte interface for intermetallic nanomaterial (iNM) electrocatalysts during CO2 reduction and to correlate these changes with catalyst performance. This project leverages the synergy between four key components: (1) machine learning-guided design and synthesis of iNM catalysts; (2) operando electron and X-ray microscopy techniques for nanoscale visualization of catalyst evolution, including electrochemical cell transmission electron microscopy (EC-TEM) and transmission X-ray microscopy (TXM); (3) development of in situ liquid cells with ultra-thin membrane windows to enhance spatial resolution and chemical sensitivity, aiming to achieve roughly 1-nm resolution in liquid environments; and (4) integration of real-time product analysis, adapting differential electrochemical mass spectrometry (DEMS) concepts for CO2 reduction. By bridging the gap between atomic-scale structural investigations and practical catalyst performance in CO2 electrolyzers, this research aims to accelerate the development of high-performing iNM-based e-CO2RR systems, potentially transforming the approach to carbon dioxide utilization and sustainable energy production. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.