In recent decades, with population growth and rapid industrialization, the contamination of water resources has become a pressing concern, with organic pollutants, heavy metals, and other complex compounds playing a significant role. Consequently, the development of novel materials that can harness natural energy and employ it for wastewater treatment represents a crucial objective. In this study, a PVDF/BaTiO3 composite membrane was synthesized via the electrospinning method. The synthesized materials were subjected to investigation by means of scanning electron microscopy (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS). The incorporation of BaTiO3 resulted in a notable reduction in fiber diameter, with a 2.9-fold decrease observed. Fourier transform infrared spectroscopy (FTIR) revealed that the β-phase fraction decreased from 87.3 to 74.3

BiFeO 3 films were obtained using the atomic layer deposition method on the surface of TiO 2 (Nt)/Ti nanotubes.After thermal treatment, the Aurivillius phase self-organizes at the film-substrate interface.During the anatase-rutile phase transformation, a redistribution of Fe-Ti atoms occurs.Local inhomogeneities and charge capture centers are formed in the sample.Studies of the memristive properties of the obtained samples showed the nonlinear nature of the current-voltage characteristic.The resulting structure can be used as a non-volatile memory with low resistive switching fields.As is known, the main requirements for the next generation of non-volatile memory begin

Селимов Д.А., Рабаданова А.А., Шуайбов А.О., Абдурахманов М.Г., Р.Р.Гюлахмедов, Рамазанов Ш

In this study, polyvinylidene fluoride (PVDF) fibers doped with hydrated calcium nitrate were prepared using electrospinning. The samples were analyzed using scanning electron microscopy (SEM), X-ray diffraction (XRD), optical spectroscopy, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR), Raman, and photoluminescence (PL) spectroscopy. The results are complementary and confirm the presence of chemical hydrogen bonding between the polymer and the dopant. Additionally, there was a significant increase in the proportion of the electroactive polar beta phase from 72 to 86%. It was shown that hydrogen bonds acted as a transport pathway for electron capture by the conjugated salt, leading to more than a three-fold quenching of photoluminescence. Furthermore, the optical bandgap of the composite material narrowed to the range of visible light energies. For the first time, it the addition of the salt reduced the energy of the PVDF exciton by a factor of 17.3, initiating photocatalytic activity. The calcium nitrate-doped PVDF exhibited high photocatalytic activity in the degradation of methylene blue (MB) under both UV and visible light (89 and 44%, respectively). The reaction rate increased by a factor of 2.4 under UV and 3.3 under visible light during piezophotocatalysis. The catalysis experiments proved the efficiency of the membrane design and mechanisms of catalysis are suggested. This study offers insight into the nature of chemical bonds in piezopolymer composites and potential opportunities for their use.

A piezoactive nanofiber composite PVDF film with TiO2 nanoparticles included in it was synthesized by electrospinning. The composition, morphology and structure of the films were investigated. The high efficiency of films in the processes of piezophotocatalytic decomposition of organic dye in water is shown.

Абдурахманов М.Г., Гюлахмедов Р.Р., Набиева Д.Ю., Рабаданова А.А., Селимов Д.А., Шуайбов А.О., Алиханов Н.М.-Р., Исаев А.Б., Рамазанов Ш.М., Оруджев Ф.Ф

By atomic layer deposition synthesis route has been performed to obtain perovskite/TiO2 nanotubes heterostructure. Perovskite nanolayer were grown on the surface of TiO2 nanotubes. UV-visible (UV-vis) diffuse reflectance spectroscopy indicated that the absorption spectrum of the perovskite/TiO2 composite extended into the visible-light region. The optical energy band gap for direct E-g1(opt) and indirect E-g2(opt) transition was determined for the perovskite/TiO2 composite which is 2,67 and 2,31 eV, respectively. (C) 2019 Elsevier Ltd. All rights reserved. Selection and peer-review under responsibility of the scientific committee of the NANOSMATAFRICA-2018.

In this work, atomic-layer deposition (ALD) of yttrium oxide (Y 2 O 3 ) was demonstrated using tris(butylcyclopentadienyl)yttrium (Y(CpBut) 3 ) and H 2 O . Yttrium precursor showed thermal stability and a high reactivity in surface reactions with H 2 O. In situ monitoring of the deposition process by quartz crystal microbalance (QCM) showed that the growth of oxide is accompanied by the absorption of water into the bulk of the film, which can lead to chemical vapor deposition (CVD) type processes. Reducing amount of dosed water as well as purge time extension during ALD cycling allow to mitigate the CVD effects. The Y 2 O 3 film growth rate 230°C varied depending on the number of cycles and had maximum value of 1.7 Å/cycle. The films obtained at 230°C had a cubic polycrystalline structure with an average density of 96% of the Y 2 O 3 bulk density. The X-ray photoelectron spectroscopy (XPS) measurements showed a carbon impurity level below the detections limit (~0.2 at %). The O/Y atomic concentration ratio estimated by Rutherford backscattering spectroscopy (RBS) was ~1.58. As deposited Y 2 O 3 films had a refractive index of 1.85 (at 632.8 nm), whereas with protective ALD Al 2 O 3 film, the refractive index was 1.73.

The magnetically separable nanophotocatalyst BiFeO3 were synthesis via facile one-step the self-propagating combustion of solutions method. It is shown that this method can be used to synthesize a phase homogeneous and nanosized powder with a BiFeO3 phase purity 99%. The effect of heat treated temperature on the morphology, structure and optical properties of BiFeO3 is investigated. The optimal parameters of heat treating temperature for the application of BiFeO3 as a photocatalyst are established. Using Mulliken's electronegativity theory, a possible mechanism of methyl orange (MO) decomposition was established. It is shown that the most probable is the oxidation of MO by hydroxyl radicals.

Aluminum nitride (AlN x ) films were obtained by atomic layer deposition (ALD) using tris(diethylamido) aluminum(III) (TDEAA) and hydrazine (N2H4) or ammonia (NH3). The quartz crystal microbalance (QCM) data showed that the surface reactions of TDEAA and N2H4 (or NH3) at temperatures from 150 to 225°C were self-limiting. The rates of deposition of the nitride film at 200°C for systems with N2H4 and NH3 coincided: ~1.1 Å/cycle. The ALD AlN films obtained at 200°C using hydrazine had higher density (2.36 g/cm3, 72.4% of bulk density) than those obtained with ammonia (2.22 g/cm3, 68%). The elemental analysis of the film deposited using TDEAA/N2H4 at 200°C showed the presence of carbon (~1.4 at %), oxygen (~3.2 at %), and hydrogen (22.6 at %) impurities. The N/Al atomic concentration ratio was ~1.3. The residual impurity content in the case of N2H4 was lower than for NH3. In general, it was confirmed that hydrazine has a more preferable surface thermochemistry than ammonia.

Epitaxial layers of the (SiC)1 − x (AlN) x solid solution with x ≈ 0.12 and x = 0.64 without macroscopic structural distortions were grown using a new technique. It was established that the compositional dependences of crystal lattice parameters of the epitaxial films obey the Vegard’s law with an error of ∼0.03. This confirms that there is formation of isomorphic substitutional solid solutions in the SiC-AlN system.

Epitaxial layers of silicon carbide of the 3C-polytype are prepared by magnetron sputtering on Si(111) substrates of structural perfection with ωθ = 1.4°. The crystalline structure and surface morphology of the 3C-SiC/Si(111) heterostructures depending on film thickness are studied by X-ray diffraction, Raman scattering, and atomic-force microscopy. It is found that the additional energy of ionized particles that is imparted to the Si(111) substrate during magnetron sputtering contributes the formation of strong C-C and β-SiC bonds, which hinders the crossing of the grain boundary by dislocations with increasing growth time.

The heterostructures of p-(SiC)1 − x (AlN) x / n -6H-SiC are synthesized by means of sublimation epitaxy of (SiC)1 − x (AlN) semiconductor solid solutions at 6H-SiC substrates. The results of the investigation of the concentration and temperature dependences on current-voltage characteristics (CVCs) are presented. It is revealed that due to the high potential barriers the forward current is caused by the tunneling and recombination processes of charge carriers via states at the boundary surface.

We have studied the effect of growth conditions on the growth rate, chemical composition, and conductivity type of films of (SiC) 1 − x (AlN) x semiconductor solid solutions produced by sublimation epitaxy on 6 H -SiC substrates in an argon + nitrogen atmosphere.