Solid-state heterogeneous Cu surfaces and Cu-containing catalysts are among the most extensively studied electrochemical systems for the CO2 reduction reaction (CO2RR). However, reported electrocatalytic studies of the CO2RR by Cu catalysts under putatively identical conditions can show large variances in product distribution. In this presentation, we share our recent efforts to quantify the role of trace metal contamination on product distributions for the CO2RR by Cu catalysts. Specifically, we show that Cu is extremely sensitive towards trace-metal impurities. In this work, we first identify the sources of trace metal contamination in a typical electrochemical cell set up, then quantify the amount of trace metal, and finally demonstrate that seemingly trivial differences in experimental set up, purity of material, and material pre-treatment can have significant impact in product distribution. In particular, we found that even ppb levels of silver metals can have dramatic effects on CO2RR product distribution—for instance, decreasing CH4 Faradaic efficiency by 19% and increasing CO efficiency by 20%.

Evaluating sources of trace metal contamination and their effect on product distribution in the Cu-catalyzed electrochemical CO2 reduction reaction

2019 Fall National Meeting

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.