Work

Unveiling co-acting effects of potassium and hydroxide ions on carbon dioxide reduction reaction selectivity

Year: 2025

Type: article

Abstract: The interfacial microenvironment plays a crucial role in influencing the absorption of important reaction intermediates and the resulting selectivity for carbon dioxide reduction reaction (CO 2 RR) (Xu et al., 2022) [1]. In this paper, the influence effects of potassium and hydroxide ions on CO 2 RR of Cu-based catalysts are comprehensively investigated using in-situ Raman spectroscopy and theoretical calculation. The results showed that potassium ions improved the binding strength of CO adsorbates (CO ad ) intermediates on active sites, which is conducive to C–C coupling or further reaction. The presence of hydroxyl adsorbates (OH ad ) changes the charge distribution on the catalyst surface and reduces the energy barrier of C–C coupling. However, the excessive OH ad adsorption can occupy a large number of active sites, leading to a decrease in CO ad coverage. We unveiled that the combined co-acting effect of potassium ions and hydroxide ions co-regulated the CO ad adsorption energy and CO ad coverage on Cu-based catalysts, leading to the modulation of the products selectivity. This work provides new insights for understanding the effect of interfacial microenvironment on the catalytic performance of CO 2 RR catalytic systems.

Source: Journal of Colloid and Interface Science

DOI: 10.1016/j.jcis.2025.02.184