In the present work thermal atomic layer deposition (ALD) of aluminum-molybdenum oxide films (AlxMoyOz) using trimethylaluminum (TMA, Al(CH3)3), molybdenum dichloride dioxide (MoO2Cl2) and water was studied. The possibility of ALD molybdenum oxide (MoO3) film using MoO2Cl2 and water was also examined. The film growth process was studied in situ using a quartz crystal microbalance (QCM) technique and ex situ using various spectroscopic methods. ALD of AlxMoyOz was carried out using supercycles consisting of TMA/H2O and MoO2Cl2/H2O subcycles. The subcycle ratios were 1 : 1 and 1 : 7, which are designated as 1Al1MoO and 1Al7MoO, respectively. At 150°C, film growth is linear with a growth rate of 5.39 and 7.62 Å per supercycle for 1Al1MoO and 1Al7MoO, respectively. The density of the films were 3.44 and 3.80 g/cm3 for 1Al1MoO and 1Al7MoO, respectively. The 1Al1MoO film with a thickness of 215.8 Å had a roughness of 10–12 Å, and the film obtained from the 1Al7MoO process with a thickness of 228.7 Å had a roughness of 16–18 Å. The synthesized thin films were characterized with XPS, XRR, SE, and XRD. The oxidation state of molybdenum in the AlxMoyOz films is +6, +5, and +4. X-ray diffraction analysis showed that the films had an amorphous structure.

In this work, quantum chemical modeling was applied to study the surface reactions of molecular layering of molybdenum (VI) oxide on the surface of β-cristobalite and amorphous monolayers of MoOx and AlOx on β-cristobalite using gaseous MoOCl4, MoO2Cl2, and H2O as reagents. Using the generalized gradient approximation method of density functional theory, the Gibbs energy changes of the molecular layering reactions (ΔG°) in the temperature range from 273.15 to 650.15 K were calculated. The calculations were carried out considering the aggregate state of the reacting substances — in the approximation of an ideal gas for gaseous substances and excluding the translational and rotational contributions for the solid phase components. According to the obtained data, the highest reactivity of the surface of the amorphous aluminum oxide monolayer on β-cristobalite is predicted in the considered temperature range. Additionally, it was found that the MoOCl4 compound has greater chemical activity compared to MoO2Cl2 towards the studied substrates. An explanation is provided for the absence of molybdenum oxide structure growth on the surface of β-cristobalite and the possible reasons for the higher reactivity of the aluminum oxide monolayer compared to the β-cristobalite surface and the amorphous MoOx monolayer. Our computational approach can generally aid in understanding the fundamental aspects of nucleation and growth of MoO3 films and mixed oxide materials like AlxMoyOz on various surfaces. Additionally, the vibrational mode frequencies in molybdenum-containing structures on the substrate surfaces were calculated in the anharmonic approximation: vSi-O-Mo = 901-1002 cm⁻1, vAl-O-Mo = 921-1015 cm⁻1, vMo-O-Mo = 716-889 cm⁻1, vMo=O = 972-1010 cm⁻1. For citation: Gadjimuradov S.G., Suleymanov S.I., Maksumova A.M., Drozdov Ye.O., Abdulagatov I.M., Abdulagatov A.I. Thermodynamic modeling of the processes of molecular layering of MoO3 on β-cristobalite and monolayers of MoOx and AlOx by the DFT method: comparative evaluation of the reactions of MoOCl4 and MoO2Cl2 with H2O. ChemChemTech [Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol.]. 2025. V. 68. N 3. P. 50-63. DOI: 10.6060/ivkkt.20256803.7132.

This work involves the ex situ characterization of molybdenum oxide (MoO 3 ) and titanium molybdenum oxide (Ti x Mo y O z ) thin films grown by atomic layer deposition (ALD) at 150°C using titanium tetrachloride (TiCl 4 ), molybdenum oxytetrachloride (MoOCl 4 ), and water. Atomic layer deposition of Ti x Mo y O z was carried out in supercycles consisting of TiCl 4 /H 2 O and MoOCl 4 /H 2 O subcycles. Two types of Ti x Mo y O z films were prepared, where the ratio of subcycles was 1 : 1 (1Ti1MoO) and 1 : 7 (1Ti7MoO). The film growth rate was determined by spectroscopic ellipsometry (SE) and X-ray reflectivity (XRR). The density and root-mean-square roughness of the films were also determined from XRR. The composition of the films was determined by X-ray photoelectron spectroscopy (XPS). The degree of oxidation of molybdenum in the MoO 3 and 1Ti7MoO films was +6, and in the 1Ti1MoO film, molybdenum was found in the oxidation states of +5 and +6. X-Ray diffraction analysis (XRD) showed that the films were amorphous.

This work demonstrates ex situ characterization of molybdenum oxide (MoO3) and titanium–molybdenum oxide (TixMoyOz) thin films obtained at 150°C by atomic layer deposition using titanium tetrachloride (TiCl4), molybdenum oxotetrachloride (MoOCl4) and water. Atomic layer deposition of TixMoyOz was carried out using supercycles consisting of TiCl4/H2O and MoOCl4/H2O subcycles. Two types of TixMoyOz films were obtained in this work, where the ratio of subcycles was 1 : 1 (1Ti1MoO) and 1 : 7 (1Ti7MoO). The film growth rate was determined by spectroscopic ellipsometry and X-Ray reflectometry. The density and root-mean-square roughness of the films were also determined by X-Ray reflectometry. The composition of the films was determined by X-Ray photoelectron spectroscopy and found that the degree of oxidation of molybdenum in the MoO3 and 1Ti7MoO films was +6, and in the 1Ti1MoO film, molybdenum was found in the oxidation state of +5 and +6. X-Ray diffraction analysis showed that the films had an amorphous structure.

This work involves the ex situ characterization of molybdenum oxide (MoO3) and titanium molybdenum oxide (TixMoyOz) thin films grown by atomic layer deposition (ALD) at 150°C using titanium tetrachloride (TiCl4), molybdenum oxytetrachloride (MoOCl4), and water. Atomic layer deposition of TixMoyOz was carried out in supercycles consisting of TiCl4/H2O and MoOCl4/H2O subcycles. Two types of TixMoyOz films were prepared, where the ratio of subcycles was 1 : 1 (1Ti1MoO) and 1 : 7 (1Ti7MoO). The film growth rate was determined by spectroscopic ellipsometry (SE) and X-ray reflectivity (XRR). The density and root-mean-square roughness of the films were also determined from XRR. The composition of the films was determined by X-ray photoelectron spectroscopy (XPS). The degree of oxidation of molybdenum in the MoO3 and 1Ti7MoO films was +6, and in the 1Ti1MoO film, molybdenum was found in the oxidation states of +5 and +6. X-Ray diffraction analysis (XRD) showed that the films were amorphous.

This work demonstrates ex situ characterization of molybdenum oxide (MoO3) and titanium–molybdenum oxide (TixMoyOz) thin films obtained at 150°C by atomic layer deposition using titanium tetrachloride (TiCl4), molybdenum oxotetrachloride (MoOCl4) and water. Atomic layer deposition of TixMoyOz was carried out using supercycles consisting of TiCl4/H2O and MoOCl4/H2O subcycles. Two types of TixMoyOz films were obtained in this work, where the ratio of subcycles was 1 : 1 (1Ti1MoO) and 1 : 7 (1Ti7MoO). The film growth rate was determined by spectroscopic ellipsometry and X-Ray reflectometry. The density and root-mean-square roughness of the films were also determined by X-Ray reflectometry. The composition of the films was determined by X-Ray photoelectron spectroscopy and found that the degree of oxidation of molybdenum in the MoO3 and 1Ti7MoO films was +6, and in the 1Ti1MoO film, molybdenum was found in the oxidation state of +5 and +6. X-Ray diffraction analysis showed that the films had an amorphous structure.

— In this paper, we report on the growth of aluminum molybdenum oxide (Al x Mo y O z ) films via atomic layer deposition (ALD) with the use of trimethylaluminum (TMA) (Al(CH 3 ) 3 ), molybdenum oxytetrachloride (MoOCl 4 ), and water. The film growth process was studied in situ using a quartz crystal microbalance and ex situ using various X-ray techniques. Al x Mo y O z ALD was performed using supercycles consisting of TMA/H 2 O and MoOCl 4 /H 2 O subcycles. We obtained two types of films, with the subcycles in the ratio 1 : 1 (1Al1MoO) and 1 : 7 (1Al7MoO). Film growth at 150°C was shown to be a linear process, with growth rate of 3.0 and 5.7 Å/supercycle for 1Al1MoO and 1Al7MoO, respectively. The density of the 1Al1MoO and 1Al7MoO films were 3.7 and 3.9 g/cm 3 , respectively, and their surface roughness did not exceed 20 Å. The oxidation state of the molybdenum in the films found to be 6+, 5+, and 4+. X-ray diffraction characterization showed that the films had an amorphous structure.

В работе продемонстрировано атомно-слоевое осаждение (АСО) алюминий-молибденовых оксидных пленок (Al x Mo y O z ) с использованием триметилалюминия (ТМА, Al(CH 3 ) 3 ), оксотетрахлорида молибдена (MoOCl 4 ) и воды. Исследование процесса роста пленок осуществляли in situ с использованием кварцевых пьезоэлектрических микровесов и ex situ рентгеновскими методами анализа тонких пленок. АСО Al x Mo y O z проводили с использованием суперциклов, состоящих из субциклов ТМА/H 2 O и MoOCl 4 /H 2 O. В работе получены два типа пленок, где соотношение субциклов составляло 1 : 1 (1Al1MoO) и 1 : 7 (1Al7MoO). При 150°C показана линейность роста пленок с постоянной роста 3.0 и 5.7 Å/суперцикл для 1Al1MoO и 1Al7MoO соответственно. Плотность полученных пленок составила 3.6 и 3.9 г/см 3 для 1Al1MoO и 1Al7MoO соответственно, а шероховатость была в пределах 20 Å. Степень окисления молибдена в полученных пленках составляла 6+, 5+ и 4+. Рентгендифракционный анализ показал, что полученные пленки имели аморфную структуру.

Titanium–vanadium oxide (TixVyOz) nanofilms were prepared by atomic layer deposition using TiCl4, VOCl3, and water. The film growth was monitored in situ by quartz crystal microbalance. At a deposition temperature of 115°С, the films grew linearly with number of deposition cycles, and the surface reactions of the precursors were self-limiting. Films of two compositions, Ti0.9V0.1O3 and Ti0.5V0.5O3, were prepared; their density was 3.5 and 3.3 g cm–3, respectively. The content of Cl impurities in the films obtained was less than 0.2 at. %, the coating roughness was ~4.0 Å, and the band gap was 3.05 and 2.85 eV for Ti0.9V0.1O3 and Ti0.5V0.5O3, respectively. All the films obtained were amorphous. The heat treatment of the Ti0.5V0.5O3 film in air led to the formation of heterostructural TiO2–V2O5 coatings. At 450°С, nanostructures consisting of anatase TiO2 and nanorods of microcrystalline V2O5 were formed. An increase in the annealing temperature to 500°С led to increase in the length of V2O5 nanowires to tens of micrometers and to their separation from the substrate, and after annealing at 550°С the substrate surface was uniformly coated with nanoparticles. The films obtained in this study can find use in the development of catalysts and power storage systems.

A study is performed of the thermal atomic layer deposition (ALD) of molybdenum oxide (MoOx) films using MoOCl4 and H2O and titanium–molybdenum oxide (TixMoyOz) thin films using TiCl4, MoOCl4, and H2O. Film growth is investigated via in situ quartz crystal microbalance (QCM) in the 115 to 180°C range of temperatures. ALD processes are considered for TixMoyOz films with different ratios of TiCl4–H2O and MoOCl4–H2O subcycles in a supercycle. The linear growth of a film upon an increase in the number of ALD cycles is in all cases established. The surface reactions of halides and H2O are shown to be of a self-limiting. The QCM data show the considered surface chemistry can be used for depositing thin MoOx and TixMoyOz films. Fields of potential application of these thin films a catalysis, electrochromic devices, lithium-ion batteries, antibacterial coatings and others.

Objective: determination of the antibacterial properties of modified TiO2 films on the colonies of Staphylococcus aureus and Escherichia coli bacteria. Comparison of antibacterial properties of samples of TiO2 films doped with different elements. Materials and methods. Synthesis and modification of TiO2 films were carried out by atomic / molecular-layer deposition in a hot-wall reactor. The antibacterial properties of the films were determined by comparing the concentrations of bacterial cultures of S. aureus and E. coli irradiated with UV and natural light in the presence of TiO2 films with the control. Results. The lowest concentration of bacterial cultures after the incubation period was in the case of the TiON and TiAlN samples, which indicates that they are the most effective. The samples of TiN and V2O5: TiO2 films showed relatively high activity. In the case of undoped TiO2, the lowest activity was observed compared to other samples, which confirms the absence of antibacterial properties for TiO2 in the visible spectra. Cunclusion. The tested samples of TiO2-based thin films (doped with N, C and vanadium), obtained by Atomic and Molecular Layer Deposition Techniques, have high antibacterial activity against bacterial cultures of sanitary indicative microorganisms Staphylococcus aureus and Escherichia coli.

Цель: определение антибактериальных свойств модифицированных пленок TiO2 на колониях бактерий Staphylococcus aureus и Escherichia coli. Сравнение антибактериальных свойств образцов пленок TiO2 легированных разными элементами. Материалы и методы. Синтез и модификация пленок TiO2 осуществлены методами атомно/молекулярнослоевого осаждения в ректоре с горячими стенками (hotwall reactor). Антибактериальные свойства пленок определены путем сравнения концентрации бактериальных культур S. aureus и E. coli облученных УФ и естественным светом в присутствии пленок TiO2 с контролем. Результаты. Наименьшее количество бактериальных культур после инкубациионного периода было в случае образцов TiON и TiAlN, что свидутульствует об их наибольшей антибактериальной. Относительно высокую активность проявили образцы пленок TiN и V2O5:TiO2. В случае недопированного TiO2 наблюдалась наименьшая активность по сравнению с другими образцами, что подтверждает отсутствие антибактериальных свойств для TiO2 в видимой области солнечного света. Заключение. Испытанные образцы тонких пленок на основе TiO22 (легированные N, C и ванадием), полученных методами АСО и МСО, обладают высокой антибактериальной активностью по отношению к бактериальным культурам санитарнопоказательных микроорганизмов S. aureus и E. coli.

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.

This work presents the results of the study of the antibacterial properties of samples of TiO2, TiON, TiN, TiAlN, TiO2:V2O5 ultrathin films synthesized by Atomic and Molecular Layer Deposition (ALD/MLD) techniques. The studies were conducted on the colonies of the E. coli and S.aureus bacteria. It was found that samples of TiON films exhibit the greatest antibacterial activity. After an hour of exposure of the TiON samples under UV light with 365 nm wave length in presence of colonies of E. coli bacteria, the activity was 93.32%, and under normal daylight it was 74.60%, which is higher than for undoped TiO2 samples with activity of 53.80% in UV light and 21.1% in daylight. Similar results were obtained with colonies of S.aureus bacteria, where the efficiency values were slightly lower due to the higher viability of these bacteria.