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Fe1/h-BN single atom catalysts can be successfully synthesized using heat treatment of Fe phthalocyanine decorated h-BN in an oxygen atmosphere. Selectivity toward hydrocarbons can be controlled by the presence of Fe nanoparticles.

Control of a single ionic charge state by altering the number of bound electrons has been considered as an ultimate testbed for atomic charge-induced interactions and manipulations, and such subject has been studied in artificially deposited objects on thin insulating layers. We demonstrate that an entire layer of controllable atomic charges on a periodic lattice can be obtained by cleaving metallic Co

Here we propose new structures which can be represented as metallocene molecules organized into a 2D hybrid structure with two carbon layers and metal atoms sandwiched between them. We called them 2D metallocene-like structures or metal-intercalated bilayer graphene allotropes inspired by MCp2 structure. The Co and Fe metal atoms as filler between the carbon layers were considered. In addition to intriguing geometry, proposed structures show dynamical stability, which was studied by state-of-the-art computational techniques. The nature of metal-carbon bonding was determined and analyzed. Half-metallic properties were observed in the case of cobalt-containing structures. Localization of magnetic moments on individual cobalt atoms opens broad prospects for application in spintronics devices due to the shielding of a magnetic metal atom by the carbon network.

Herein we report a simple and easily scalable method for fabricating ZnO/

The structural and physicochemical properties of the MoSe2/PTCDA heterostructure, which consists of two-dimensional inorganic and molecular organic semiconductors, have been studied theoretically. Features of change in the electronic properties of the PTCDA monomolecular layer on the MoSe2 surface have been described by density functional theory. The quantitative analysis of charge transfer between the heterostructure components has explained the features of coupling between the layers. The study of the optical characteristics of the heterostructure has revealed the enhancement of the absorption spectrum in the infrared range. Consequently, MoSe2/PTCDA heterostructures are promising for applications in electronics, optoelectronics, and materials for the utilization of solar energy.

The elastic and plastic deformation of Ta2Pd3Se8 and Ta2Pt3Se8 nanoribbons under uniaxial tension was studied. It was found that TPS nanoribbons have high values of critical strain corresponding to...

Magnetic halogen doped MoX2 (X = S and Se) monolayers influenced the electronic structure of graphene through a proximity effect. This process was observed using state-of-the-art calculations. It was found that the substitution of a single chalcogen atom with a halogen atom (F, Cl, Br, and I) results in n-type doping of MoX2. An additional electron from the dopant is localized on binding orbitals with the nearest Mo atoms and leads to the formation of magnetism in the dichalcogenide layer. Detailed analysis of halogen doped MoX2/graphene heterostructures demonstrated the induction of spin polarization in graphene near the Fermi energy. Significant spin polarization near the Fermi energy and n-type doping were observed in the graphene layer of MoSe2/graphene heterostructures with MoSe2 doped with iodine. At the same time, fluorine-doped MoSe2 does not cause n-doping in graphene, while spin polarization still takes place. The possibility for the detection of the arrangement of the halogen impurities at the MoX2 basal plane even with the graphene layer deposited on top was demonstrated through STM measurements which will be undoubtedly useful for the fabrication of electronic schemes and elements based on the proposed heterostructures for their further application in nanoelectronics and spintronics.

One dimensional Ta2(Pd/Pt)3(S/Se)8 nanoribbons (TPS-NR) are considered as a promising material in nanoelectronics due to their intrinsic semiconducting electronic properties. In this article, we study the stability of TPS-NR by considering their oxidation process. Our calculations showed that the Ta2(Pd/Pt)3Se8 nanoribbons are more environmentally stable than Ta2(Pd/Pt)3S8-NR. We studied the thermodynamics of the formation of monovacancies and their impact on the electronic properties of TPS-NR. Additionally, the sensing properties of environmentally stable Ta2Pd3Se8 nanoribbons were investigated. The observed changes of the electronic structure and transport properties after the adsorption of CO, NH3 and NO2 molecules reveal the mechanisms of possible application of Ta2Pd3Se8 nanoribbons as a gas sensor. The electronic transport properties of the nanoribbons exhibit a notable response to the presence of gas molecules.

Intercalation raises manifold possibilities to manipulate the properties of two-dimensional (2D) materials1, and its impact on local electronic/magnetic properties has drawn much attention with the rise of nano-structured 2D materials2,3. Typically, changing an ionic state in a solid involves a dramatic local change of energy as well as orbital/spin magnetic moment from its ground state. However, the atomic investigation of the charging process of an intercalant ion in 2D material has never been explored while such subject has been studied in artificially deposited atoms on thin insulating 2D layers using scanning probe microscopy4–7. Herein, we demonstrate an atomical manipulation of the charge and spin state of Co ions on a metallic NbS2, obtained by cleaving of Co-intercalated NbS2. Density functional theory investigation of various Co configurations reveals that the charging is possible due to a change in the crystal field at the surface and a significant coupling between NbS2 and intercalants occurs via orbitals of the a1g symmetry. The results can be generalized to numerous other combinations of intercalants and base matrixes, suggesting that intercalated transition metal dichalcogenides can be a new platform to introduce single-atom operation 2D electronics/spintronics.

Herein we analyzed the chemical reactions occurring in the process of Ag/BN hybrid fabrication in polyethylene glycol (PEG) using h-BN nano- and microparticles (BNNPs and BNMPs) during AgNO3 decomposition under UV irradiation. Decomposition of AgNO3 causes formation of Ag nanoparticles (AgNPs) and PEG oxidation reaction, the products of which interact with Ag to form Ag acetate. The polymer matrix surrounding AgNPs prevents their growth during the fabrication process. Additional low temperature annealing leads to the decomposition of the Ag acetate phase, thereby increasing the volume fraction of AgNPs. In the case of the BNNPs, the AgNP size is smaller and their distribution is more homogeneous. BNNP surface oxidation was shown to be an important factor leading to enhanced catalytic activity of Ag/BN hybrids in the CO oxidation reaction: Tinitiation = 150 °C and T100 = 200 °C. Theoretical modelling suggests that the high catalytic activity of Ag/BN nanohybrids (NHs) can be explained by the formation of thin B–O–Ag layers.

One dimensional Ta2(Pd/Pt)3(S/Se)8 nanoribbons (TPS-NR) are considered as a promising material in nanoelectronics due to their intrinsic semiconducting electronic properties. In this article, we study the stability of TPS-NR by considering their oxidation process. Our calculations showed that the Ta2(Pd/Pt)3Se8 nanoribbons are more environmentally stable than Ta2(Pd/Pt)3S8-NR. We studied the thermodynamics of the formation of monovacancies and their impact on the electronic properties of TPS-NR. Additionally, the sensing properties of environmentally stable Ta2Pd3Se8 nanoribbons were investigated. The observed changes of the electronic structure and transport properties after the adsorption of CO, NH3 and NO2 molecules reveal the mechanisms of possible application of Ta2Pd3Se8 nanoribbons as a gas sensor. The electronic transport properties of the nanoribbons exhibit a notable response to the presence of gas molecules.

NaCl is one of the simplest compounds and was thought to be well-understood, and yet, unexpected complexities related to it were uncovered at high pressure and in low-dimensional states. Here, exotic hexagonal NaCl thin films on the (110) diamond surface were crystallized in the experiment following a theoretical prediction based on

The iron silicides formation during epitaxial film grown process on the (100) and (111) silicon surfaces were investigated using molecular dynamics (MD). The iron and silicon atom deposition rate and silicon substrate temperature influence on the formed iron silicide structure and stoichiometric composition were studied in detail. During the growth of iron silicide crystal structure significant diffusion of the substrate atoms into the forming BCC core occurs, this intensifies with the substrate temperature increase, and the ratio of substrate atoms inside the Fe3Si phase reaches nearly 12%. The BCC structure formation is less active on the (100) surface, and at the temperatures as low as 26 °C and 300 °C the iron silicide crystal phase does not form at all. However, with the temperature increase or the deposition rate decrease, the crystal structure formation processes occur more actively in both cases of (100) and (111) surfaces. Thus, the effect of the deposition rate decrease is identical to the temperature growth. It was shown that the formation of the structured B2 phase of iron silicide in buffer layer between the film and the substrate leads to the inhibition of the mutual diffusion of iron and silicon atoms.

This work is aimed at the development of bimetallic (Ni0.2Cu0.8) catalysts with hexagonal boron nitride (h-BN) nanosheet (BNNS) supports and elucidating their catalytic activity in the methanol steam reforming and CO oxidation reactions. The hybrid Ni0.2Cu0.8/BN catalysts consist of curved h-BN nanosheets, up to 10–20 nm in lateral size, decorated with metallic nanoparticles, 3.0–8.2 nm in dimensions. The methanol conversion starts at ~20 °C and is nearly completed at 320 °C. The (Ni0.2Cu0.8)/BN nanohybrids exhibit high catalytic stability and high selectivity for CO2 over the whole temperature range. No carbon monoxide is detected during full methanol conversion. The possible mechanism of CO utilization during methanol reforming is proposed using ab initio calculations. The onset temperature of catalytic CO oxidation is 100 °C and full conversion is completed at 200 °C. These results indicate high catalytic efficiency of (Ni0.2Cu0.8)/BN nanohybrids in methanol steam reforming and CO oxidation reactions.

Difluorinated higher fullerenes have been studied by Knudsen cell mass spectrometry. Thermal negative ions C n F 2 − ( n =60, 70, 72, 74, 76 and 78) were produced inside the effusion cell as well as the neutral molecules C 60 F 2 and C 70 F 2 . From the equilibrium constants for the electron exchange reactions between difluorinated fullerenes and their parents electron affinity values were derived for C 60 F 2 (2.74 eV) and C 70 F 2 (2.80 eV).