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Recently, the research of two-dimensional layered transition metal dichalcogenides has made great progress due to their high potential in advanced electronic devices. In this work, H-phase VS2 atomic layers with different morphologies and stacking orders were successfully synthesized on sapphire via chemical vapor deposition. The H-phase VS2 shows semiconductor characteristic with its valence band maximum located ~ 0.25 eV below the Fermi level. Interlayer many-body interactions are strongly stacking-dependent, leading to distinguished intensity ratio between the breathing and shear modes, 2.99 ± 0.94 for AA, and 1.72 ± 0.26 for AB stacking. The intralayer S-V interaction (force constant: 2.80–3.54 × 1021 N/m3) is two orders of magnitude larger than the interlayer S–S interaction (force constant: 1.98–6.70 × 1019 N/m3). The shear modulus is further derived to be ~ 12.8 GPa, ~ 30% smaller than that of MoS2. The prepared VS2 film exhibits obvious magnetic behavior at room temperature with the attenuation distance of ~ 16–25 nm in out-of-plane direction. The morphology dependent magnetism and stability investigations indicate that the measured magnetic behaviors of the sample have a certain degree of extrinsic contributions, which may settle down some experimental controversies about the magnetic behaviors in this specific system. [ABSTRACT FROM AUTHOR]

Hexagonal vaterite-type LuBO:Tb/Eu lantern-like phosphors have been successfully prepared by a simple hydrothermal process directly without sintering treatment. X-ray diffraction, scanning electron microscopy, transmission electron microscopy, high-resolution transmission electron microscopy, selected area electron diffraction, photoluminescence, low-voltage cathodoluminescence, and kinetic decays were used to characterize as-prepared phosphors, which present complex lantern-like 3D assemblies that are composed of nanosheets with thickness of about 23 nm and high crystallinity in spite of the moderate reaction temperature of 210 °C. The reaction mechanism and the self-assembly evolution process have been proposed. The pH, temperature, time, and ethylene glycol play critical roles in the formation of this specific hierarchical and complex 3D structure. Under UV excitation and low-voltage electron beam excitation, vaterite-type LuBO:Tb samples showed the characteristic green emission of Tb corresponding to D → F transitions; vaterite-type LuBO:Eu particles exhibited a strong red emission corresponding to primary group electric dipole transition D → F with much higher R/O values (chromatically redder fluorescence, increase of 29 %) compared with samples by conventional solid-state reaction, which have potential applications in fluorescent lamps and field emission displays. [ABSTRACT FROM AUTHOR]