Germanene Reformation from Oxidized Germanene on Ag(111)/Ge(111) by Vacuum Annealing.

For group 14 mono-elemental 2D materials, such as silicene, germanene, and stanene, oxidation is a severe problem that alters or degrades their physical properties. This study shows that the oxidized germanene on Ag(111)/Ge(111) can be reformed to germanene by simple heating ≈500 °C in a vacuum. The key reaction in reforming germanene is the desorption of GeO and GeO during heating ≈350 °C.

Growth of a quasicrystal-related structure and superstructure for ultrathin Ce-Ti-O films on Pt(111).

Herein, oxide quasicrystal-related (OQC-R) structure and Ce-Ti-O-(3 × 3) superstructure ultrathin films were prepared on Pt(111) and characterized using scanning tunneling microscopy (STM) and low-energy electron diffraction. The OQC-R structure with dodecagonal clusters consisting of triangles, squares, and rhombuses was observed in STM images. The first discovery of the OQC-R structure with a magnetic rare earth metal expands the possibility of discovering new oxide quasicrystals with novel magnetism or superconductivity.

Graphene's Latest Cousin: Plumbene Epitaxial Growth on a "Nano WaterCube".

While theoretical studies predicted the stability and exotic properties of plumbene, the last group-14 cousin of graphene, its realization has remained a challenging quest. Here, it is shown with compelling evidence that plumbene is epitaxially grown by segregation on a Pd Pb (111) alloy surface. In scanning tunneling microscopy (STM), it exhibits a unique surface morphology resembling the famous Weaire-Phelan bubble structure of the Olympic "WaterCube" in Beijing.

Germanene Epitaxial Growth by Segregation through Ag(111) Thin Films on Ge(111).

Large-scale two-dimensional sheets of graphene-like germanium, namely, germanene, have been epitaxially prepared on Ag(111) thin films grown on Ge(111), using a segregation method, differing from molecular beam epitaxy used in previous reports. From the scanning tunneling microscopy (STM) images, the surface is completely covered with an atom-thin layer showing a highly ordered long-range superstructure in wide scale. Two types of protrusions, named hexagon and line, form a (7√7 × 7√7) R19.

Growth and structure of ultrathin cerium oxide films on Rh(111).

The geometric structure of ultra-thin cerium oxide films on Rh(111), prepared by annealing the metallic cerium films at a very low coverage between 0.3 and 1.5 monolayers in an oxygen atmosphere, is investigated using scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), X-ray photoelectron spectroscopy, and density functional theory (DFT) calculations.