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Stanene, which is predicted to be a quantum spin Hall topological insulator with tunable topological state, seems to be the most promising candidate of the post-graphene elemental two-dimensional (2D) materials. Here, we prepared epitaxial honeycomb-like stanene on gold (111) substrates and investigated its superstructure by Low Energy Electron Diffraction and Scanning Tunneling Microscopy. Angle-Resolved PhotoEmission Spectroscopy was applied to explore the electronic structures, further confirmed by first principles calculations. The stanene-like sheet forms a nearly planar structure on the Au(111) surface with a "2×√3" superstructure in large surface areas. Core-level spectroscopy reveals that the stanene-like sheet lays almost directly on the Au(111) surface. This is consistent with DFT calculations of the atomic structure. A characteristic 2D band with parabolic dis-persion is observed.

The cathode/anode-electrolyte interfaces in lithium/sodium ion batteries act as the “gate” for the ion exchange between the solid electrode and liquid electrolyte. Understanding the interfacial properties of these solid-liquid interfaces is essential for better design high-performance lithium/sodium ion batteries. Here, we provide a novel method for studying solid-liquid interfacial properties of battery materials through combining physical vapor deposition (PVD) and beam-exit cross-sectional polishing (BEXP) followed by controlled environment multifunctional Scanning Probe Microscope (SPM). In this method, commercial battery materials can be either directly grown on the current collector substrates, or polished by obliqued Ar-ion beams to get a nanoscale flat surface which allows the multifunctional SPM to study sample directly in the liquid electrolyte or in protective oxygen/H 2 O free environment. This approach allows to investigate wide range of interfacial properties, including surface morphology, internal cracks, mechanical properties, electronic/ionic conductivity and surface potential, with nanoscale resolution in-operando during the battery cycles as well as post-mortem. PVD and novel BEXP methods were introduced to prepare battery powder materials as perfect specimens for nanoscale SPM characterization. Various physical/chemical properties of battery materials can be probed on the as-prepared specimens under liquid electrolyte using in situ/operando SPM techniques. Ex situ/post-mortem analyses based on the controlled environment multifunction SPM characterizations can be achieved in the BEXP polished degradation battery electrodes.

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Argentum-doped zinc selenide/silicon dioxide nanoparticles (expressed as ZnSe: Ag/SiO2) were synthesized by Stöber method. The structure, morphology and fluorescence properties of the quantum dots were characterized by X-ray powder diffraction, transmission electron microscopy, infrared spectrum, ultraviolet-visible spectrum and fluorescence spectrum. The results show that the as-prepared ZnSe: Ag/SiO2 nanoparticles are spherical, most of which are about 30 nm in size, and have good fluorescence properties. Compared with that of ZnSe: Ag nanoparticles, the stability of ZnSe: Ag/SiO2 nanoparticles is enhanced obviously. The ZnSe: Ag/SiO2 nanoparticles will have potential applications in biological fluorescence analysis.