Pushing the Ag-Loading of CO2 Electrolyzers to the Minimum via Molecularly Tuned Environments

Abstract

Electrochemically converting CO2 to renewable synthons is steadily becoming a globally scalable and important CO2 utilization technology. Nevertheless, most industrial endeavors employ critical-materials catalysts based on Ag or Au, with catalytically competitive alternatives, showing both similar activity and high mass activity and cost-efficiency remaining elusive. Similarly, this effort is hindered by insufficient testing of promising materials in application-oriented conditions. We herein present a holistic pathway starting the conceptualization of different Ag(I)-based molecular catalysts to their complete integration into directly industrially applicable cells assemblies. Notably, optimization of not only the catalyst but also the operational conditions allowed us to reach catalytic activity for CO formation close to 1 A cm-2, the performance of efficient CO2 electrolysis for at least 110 h, while achieving one of the highest mass activities reported for CO at 101636 mA mgAg‑1, accompanied by cost decreases up to a factor of 80 against the current heterogeneous standards.

Keywords: CO2 electrolysis, zero-gap electrolyzers, molecular electrocatalysts, BIAN, silver