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The synthesis of vertical ReS₂ nanowalls on 3D graphene foam (V-ReS₂/3DGF) is demonstrated by a chemical vapor deposition route. The vertical nanowall structure leads to an effective exposure of active sites and enhances the lithium interaction with all of the layers. When serving as the anode material for lithium-ion batteries, the V-ReS₂/3DGF composite demonstrates excellent cycling stability at high-current-density.

Layer specific direct measurement of optical band gaps of two important van der Waals compounds, MoS2 and ReS2, is performed at nanoscale by high resolution electron energy loss spectroscopy. For monolayer MoS2, the twin excitons (1.8 and 1.95 eV) originating at the K point of the Brillouin zone are observed. An indirect band gap of 1.27 eV is obtained from the multilayer regions. Indirect to direct band gap crossover is observed which is consistent with the previously reported strong photoluminescence from the monolayer MoS2. For ReS2, the band gap is direct, and a value of 1.52 and 1.42 eV is obtained for the monolayer and multilayer, respectively. The energy loss function is dominated by features due to high density of states at both the valence and conduction band edges, and the difference in analyzing band gap with respect to ZnO is highlighted. Crystalline 1T ReS2 forms two dimensional chains like superstructure due to the clustering between four Re atoms. The results demonstrate the power of HREELS technique as a nanoscale optical absorption spectroscopy tool.

Forensic fingerprint-age estimation is currently impossible. Knowledge on time passed since fingerprint deposition is desired as it can distinguish between crime-related and unrelated fingerprints and support or refute statements made by fingerprint donors. In their Communication on page 6272 ff., S. A. G. Lambrechts and co-workers describe a successful fluorescence-based method to estimate fingerprint age that relies on the protein–lipid oxidation rate and the subsequent generation of fluorescent oxidation products.

The structure and electronic structure of layered noble-transition-metal dichalcogenides MX₂ (M=Pt and Pd, and chalcogenides X=S, Se, and Te) have been investigated by periodic density functional theory (DFT) calculations. The MS₂ monolayers are indirect band-gap semiconductors whereas the MSe₂ and MTe₂ analogues show significantly smaller band gap and can even become semimetallic or metallic materials. Under mechanical strain these MX₂ materials become quasi-direct band-gap semiconductors. The mechanical-deformation and electron-transport properties of these materials indicate their potential application in flexible nanoelectronics.

Show you're metal: The structure and electronic structure of layered noble-transition-metal dichalcogenides MX₂ with metals M (Pt and Pd) and chalcogenides X (S, Se, and Te) have been investigated with periodic density functional theory calculations. The MS₂ monolayers are indirect band-gap semiconductors whereas the MSe₂ and MTe₂ analogues show a significant decrease in their band-gaps and can even become semimetallic or metallic materials.