Understanding the Unique Reactivity of Cu for Electrochemical CO Reduction with a 3-Site Model.

Cu-based catalysts for the electrochemical reduction of CO and CO exhibit a perplexingly unique reactivity toward multicarbon based products compared to other studied electrocatalysts. Here we use insights gained from a recent phenomenological 3-site microkinetic model and grand-canonical density functional theory calculations to clarify the importance of an underemphasized aspect critical to Cu's unique reactivity: a population of so-called "reservoir" sites. Using model Cu surface motifs, we discuss how these types can be represented by undercoordinated structural defects like step edges and grain boundaries which form a network of highly anisotropic migration channels.

Sphingosine-1-Phosphate Signalling Inhibition Suppresses Th1-Like Treg Generation by Reversing Mitochondrial Uncoupling.

Inflammatory environments induce the generation of dysfunctional IFNγT-betFOXP3 Th1-like Tregs, which show defective function and are found in autoimmune conditions including multiple sclerosis (MS). The pathways that control the generation of Th1-like Tregs are not well understood. Sphingosine-1-phosphate (S1P) signalling molecules are upregulated in Th1-like Tregs, and in vivo S1P inhibition with Fingolimod (FTY720) inhibits the expression of genes responsible for Treg plasticity in MS patients.

Cu Based Dilute Alloys for Tuning the C Selectivity of Electrochemical CO Reduction.

Electrochemical CO reduction is a promising technology for replacing fossil fuel feedstocks in the chemical industry but further improvements in catalyst selectivity need to be made. So far, only copper-based catalysts have shown efficient conversion of CO into the desired multi-carbon (C) products. This work explores Cu-based dilute alloys to systematically tune the energy landscape of CO electrolysis toward C products.

Importance of Site Diversity and Connectivity in Electrochemical CO Reduction on Cu.

Electrochemical CO reduction on Cu is a promising approach to produce value-added chemicals using renewable feedstocks, yet various Cu preparations have led to differences in activity and selectivity toward single and multicarbon products. Here, we find, surprisingly, that the effective catalytic activity toward ethylene improves when there is a larger fraction of less active sites acting as reservoirs of *CO on the surface of Cu nanoparticle electrocatalysts. In an adaptation of chemical transient kinetics to electrocatalysis, we measure the dynamic response of a gas diffusion electrode (GDE) cell when the feed gas is abruptly switched between Ar (inert) and CO.