X-ray diffraction evidence is presented for the incorporation of molecular hydrogen into GaSe crystals, which markedly reduces their c -axis resistivity and shifts the excitonic line to higher energies.

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Transformation of surface nitrates under CI-I4 (CH4 + 02) was found to ensure steady-state activity of Co-ZSM-5 in the selective catalytic reduction of nitrogen oxides by methane (CI-I4-SCR). For Cu-ZSM-5, such species are mainly converted into NO. Kelaxation of the coordination sphere due to oxygen and NO adsorption, stability of C,N-containing intermediates and activation routes of hydrocarbons (methane, propane) were analyzed as factors determining catalytic properties of Cu and Co cations.

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Features of the formation of Au/Ni/〈C〉/n Ga 2 O 3 hybrid nanostructures on a Van der Waals sur face (0001) of "layered semiconductor-ferroelectric" composite nanostructures (p GaSe〈KNO 3 〉) are stud ied using atomic force microscopy. The room temperature current-voltage characteristics and the depen dence of the impedance spectrum of hybrid structures on a bias voltage are studied. The current-voltage characteristic includes a resonance peak and a portion with negative differential resistance. The current attains a maximum at a certain bias voltage, when electric polarization switching in nanoscale three dimen sional inclusions in the layered GaSe matrix occurs. In the high frequency region (f > 10 6 Hz), inductive type impedance (a large negative capacitance of structures, ~10 6 F/mm 2 ) is detected. This effect is due to spin polarized electron transport in a series of interconnected semiconductor composite nanostructures with mul tiple p GaSe〈KNO 3 〉 quantum wells and a forward biased "ferromagnetic metal-semiconductor" polarizer (Au/Ni/〈C〉/n + Ga 2 O 3 /n Ga 2 O 3 ). A shift of the maximum (current hysteresis) is detected in the currentvoltage characteristics for various directions of the variations in bias voltage.

No abstract

Self‐assembled core–shell Ni–C nanoparticles (NPs) with nearly uniform sizes were grown on the van der Waals (0001) surfaces of GaSe layered crystals. The metal NPs encapsulated within graphite shells (Ni@C) with the sizes ranging from a few to 15 nm were produced by electron beam induced vacuum deposition from metal‐carbon melts under UV‐irradiation without annealing after the deposition. The samples were characterized by X‐ray diffraction, atomic force microscopy, X‐ray photoelectron spectroscopy, Raman spectroscopy. The van der Waals interactions between the NPs and the surface electrostatic interactions are utilized for encapsulated NPs self‐assembly. The Coulomb staircases and the negative differential conductance were observed at temperatures lower than 300 K in the current–voltage (I–V) curves of the vertical hybrid structures Au/Ni/(Ni–C)/Ni@CNCs/n‐Ga2O3/p‐GaSe/In consisting of ferromagnetic metal Ni, (Ni–C) nanocomposite thin film and two layers of magnetic NPs (Ni@CNCs), which were embedded in n‐Ga2O3 wide‐band‐gap oxide. The I–V characteristics of this structure depend on orientation of the external weak (∼60 mT) magnetic field relative to the (0001) GaSe plane. Peculiarities observed in the I–V characteristics of the hybrid structures may be caused by magnetic‐field‐dependent phenomena of spin‐dependent tunneling through the barriers, which gives rise to spin accumulation, and spin‐polarized electric current interactions with magnetic NPs.

Physical mechanisms of intercalation of semiconductors are determined, establishing the main laws of intercalation, and the physical nature of new phenomena and effects induced by intercalation are explained; general statements for obtaining intercalates with characteristics assigned in advance are also developed.