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Single-walled carbon nanotubes (SWCNTs) possessing a confined inner space protected by chemically resistant shells are promising for delivery, storage, and desorption of various compounds, as well as carrying out specific reactions. Here, we show that SWCNTs interact with molten mercury dichloride (HgCl) and guide its transformation into dimercury dichloride (HgCl) in the cavity. The chemical state of host SWCNTs remains almost unchanged except for a small p-doping from the guest HgCl nanocrystals. The density functional theory calculations reveal that the encapsulated HgCl molecules become negatively charged and start interacting via chlorine bridges when local concentration increases. This reduces the bonding strength in HgCl, which facilitates removal of chlorine, finally leading to formation of HgCl species. The present work demonstrates that SWCNTs not only serve as a template for growing nanocrystals but also behave as an electron-transfer catalyst in the spatially confined redox reaction by donation of electron density for temporary use by the guests.

In this paper we show the advantages of transparent high conductive films based on filled single-wall carbon nanotubes.

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This paper reports the analysis of the intensity of diamond line in the Raman spectra of laser modified layers with different thickness on a diamond surface. Since the diamond line passing from substrate through the absorbing layer of moderate thickness can be registered, the thickness of local area is estimated from its micro‐Raman spectra. The comparison between Raman scattering and direct observation of the graphitized layer by transmission electron microscopy shows that Raman spectroscopy can be used as an alternative non‐destructive method for measuring a moderate thickness of graphitized layers.

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To transform a monocrystalline diamond into monocrystalline graphite, the exposure of an ultrafast laser to a (111) diamond face was investigated for the first time. The single pulse of the third harmonic of a Ti:sapphire laser (100 fs, 266 nm) was used to produce graphitized inclusions embedded in a (111) diamond substrate. Three different regimes of (111) diamond graphitization are discussed in this paper. Raman spectroscopy, scanning electron microscopy, and transmission electron microscopy were used to investigate the graphitized material, which was found to resemble highly oriented graphite at certain laser fluencies. The proposed approach to the problem of perfect local diamond graphitization is an important step toward creating all-carbon composite systems consisting of conductive and dielectric phases.

Atomically thin two-dimensional (2D) materials can be vertically stacked with van der Waals bonds, which enable interlayer coupling. In the particular case of transition metal dichalcogenide (TMD) bilayers, the relative direction between the two monolayers, coined as twist-angle, modifies the crystal symmetry and creates a superlattice with exciting properties. Here, we demonstrate an all-optical method for pixel-by-pixel mapping of the twist-angle with a resolution of 0.55(°), via polarization-resolved second harmonic generation (P-SHG) microscopy and we compare it with four-dimensional scanning transmission electron microscopy (4D STEM). It is found that the twist-angle imaging of WS2 bilayers, using the P-SHG technique is in excellent agreement with that obtained using electron diffraction. The main advantages of the optical approach are that the characterization is performed on the same substrate that the device is created on and that it is three orders of magnitude faster than the 4D STEM. We envisage that the optical P-SHG imaging could become the gold standard for the quality examination of TMD superlattice-based devices.