Search for: All records

Abstract The creation of metal‐metal oxide interfaces is an important approach to fine‐tuning catalyst properties through strong interfacial interactions. This article presents the work on developing interfaces between Pt and CeO_xthat improve Pt surface energetics for the hydrogen evolution reaction (HER) within an alkaline electrolyte. The Pt‐CeO_xinterfaces are formed by depositing size‐controlled Pt nanoparticles onto a carbon support already coated with ultrathin CeO_xnanosheets. This interface structure facilitates substantial electron transfer from Pt to CeO_x, resulting in decreased hydrogen binding energies on Pt surfaces, and water dissociation for the HER, as predicted by the density functional theory (DFT) calculations. Electrochemical testing indicates that both Pt specific activity and mass activity are improved by a factor of 2 to 3 following the formation of Pt‐CeO_xinterfaces. This study underscores the significance and potential of harnessing robust interfacial effects to enhance electrocatalytic reactions. 

Electroreduction of carbon dioxide (CO₂) or carbon monoxide (CO) toward C₂₊hydrocarbons such as ethylene, ethanol, acetate and propanol represents a promising approach toward carbon-negative electrosynthesis of chemicals. Fundamental understanding of the carbon─carbon (C-C) coupling mechanisms in these electrocatalytic processes is the key to the design and development of electrochemical systems at high energy and carbon conversion efficiencies. Here, we report the investigation of CO electreduction on single-atom copper (Cu) electrocatalysts. Atomically dispersed Cu is coordinated on a carbon nitride substrate to form high-density copper─nitrogen moieties. Chemisorption, electrocatalytic, and computational studies are combined to probe the catalytic mechanisms. Unlike the Langmuir-Hinshelwood mechanism known for copper metal surfaces, the confinement of CO adsorption on the single-copper-atom sites enables an Eley-Rideal type of C-C coupling between adsorbed (*CO) and gaseous [CO(g)] carbon moxide molecules. The isolated Cu sites also selectively stabilize the key reaction intermediates determining the bifurcation of reaction pathways toward different C₂₊products.