CO Adsorption on a Single-Atom Catalyst Stably Embedded in Graphene.

Confined single metal atoms in graphene-based materials have proven to be excellent catalysts for several reactions and promising gas sensing systems. However, whether the chemical activity arises from the specific type of metal atom or is a direct consequence of the confinement itself remains unclear.

Direct Electrical Access to the Spin Manifolds of Individual Lanthanide Atoms.

Lanthanide atoms show long magnetic lifetimes because of their strongly localized 4 electrons, but electrical control of their spins has been difficult because of their closed valence shell configurations. We achieved electron spin resonance of individual lanthanide atoms using a scanning tunneling microscope to probe the atoms bound to a protective insulating film. The atoms on this surface formed a singly charged cation state having an unpaired 6 electron, enabling tunnel current to access their 4 electrons.

Electrically driven spin resonance of 4f electrons in a single atom on a surface.

A pivotal challenge in quantum technologies lies in reconciling long coherence times with efficient manipulation of the quantum states of a system. Lanthanide atoms, with their well-localized 4f electrons, emerge as a promising solution to this dilemma if provided with a rational design for manipulation and detection. Here we construct tailored spin structures to perform electron spin resonance on a single lanthanide atom using a scanning tunneling microscope.

Probing Catalytic Sites and Adsorbate Spillover on Ultrathin FeO Film on Ir(111) during CO Oxidation.

The spatially resolved identification of active sites on the heterogeneous catalyst surface is an essential step toward directly visualizing a catalytic reaction with atomic scale. To date, ferrous centers on platinum group metals have shown promising potential for low-temperature CO catalytic oxidation, but the temporal and spatial distribution of active sites during the reaction and how molecular-scale structures develop at the interface are not fully understood. Here, we studied the catalytic CO oxidation and the effect of co-adsorbed hydrogen on the FeO/Ir(111) surface.