Rashid Dallaev

Brno University of Technology · Department of Physics

This study investigates the optical properties of yttrium ferrite thin films fabricated via pulse laser deposition. Yttrium orthoferrite, a ferrimagnetic material known for its potential applications in spintronics and photonics, was deposited on single-crystal substrates under controlled conditions to analyze its optical characteristics. The influ...

Polymer graphite electron sources have performed satisfactorily as field emission emitters and scanning tunneling microscopy probes in the past few years. However, the emission process was characterized by limited total emission currents. This paper introduces the elemental, vibrational, electrical, and optical analysis of polymer graphite and glas...

Nitride salts were added to polyvinylidene fluoride fibers and then the fiber mats were prepared by electrospinning. An experimental investigation of the structure was provided by Raman, FTIR, SEM, and XRD. The phase ratio of the polymer was studied both theoretically and experimentally in connection with the addition of the hydrates Mg(NO3)2, Ca(N...

This study investigates the optical properties of Yttrium Orthoferrite thin films fabricated via plasma laser deposition. Yttrium Orthoferrite, a ferrimagnetic material known for its potential applications in spintronics and photonics, was deposited on single-crystal substrates under controlled conditions to analyze its optical characteristics. The...

Hydrogen embrittlement (HE) remains a pressing issue in materials science and engineering , given its significant impact on the structural integrity of metals and alloys. This exhaustive review aims to thoroughly examine HE, covering a range of aspects that collectively enhance our understanding of this intricate phenomenon. It proceeds to investig...

The development of materials with self-healing capabilities has garnered considerable attention due to their potential to enhance the durability and longevity of various engineering and structural applications. In this review, we provide an overview of recent advances in materials with self-healing properties, encompassing polymers, ceramics, metal...

Citation: Dallaev, R.; Spusta, T.; Allaham, M.M.; Spotz, Z.; Sobola, D. Synthesis and Band Gap Characterization of High-Entropy Ceramic Powders. Crystals 2024, 14, 295. https://doi. Abstract: This manuscript presents a comprehensive exploration of the band gap structure of (CoCrFeNiMn) 3 O 4 powders through a series of experimental investigations....

The absorption coefficient plays an important role in studying and characterizing semiconducting materials. It is an important parameter to study the mechanism of photons absorption within the structure of the studied material. Thus, it helps to study the several types of charge carrier transport along with the energy band structure and its defects...

This article shortly describes the structure of the butterflies’ wings scales, their variations and properties. Experimental data obtained herein using an atomic force microscope (AFM) instrument sheds some light on the Coenonympha pamphilius scaly wing structure. Coenonympha pamphilus is the smallest butterfly of Satyrinae subfamily and is otherwi...

Butterflies have color vision which they utilize in the search for flowers. There are typically around six difference classes of photoreceptors with specific spectral sensitivities. This paper goes over a typical butterflies’ eyes structure as well as their properties. The experimental data obtained using an atomic force microscope was used to inve...

This paper offers a short overview of epoxy resins, encompassing their diverse characteristics, variants, chemical modifications, curing processes, and intriguing electrical properties. Epoxies, valued for their multifunctional attributes, serve as fundamental materials across industries. In the realm of dielectric strength, epoxy resins play a cru...

The rapid growth and evolution of solar panel technology have been driven by continuous advancements in materials science. This review paper provides a comprehensive overview of the diverse range of materials employed in modern solar panels, elucidating their roles, properties, and contributions to overall performance. The discussion encompasses bo...

This work focuses on the unexplored synthesis and material analysis of the composite based on nanofibers of the thermoplastic polymer called polyvinylidene fluoride (PVDF) and iron-based metal-organic framework (MOF) nanoparticles. In addition to high durability, PVDF has piezoelectric properties. When synthesized as nanofibers, it also provides a...

The concept of the Internet of Things is capable of making a giant leap in the economy, including research in the field of computer science, network technologies, microelectronics and sensor technology. Combined with the technological developments of nanotechnology and robotics, IoT can play a central role in the industrial revolution by creating e...

Bismuth ferrite (Bi–Fe–O)-based compounds have a wide range of features that are of interest both for basic science and applied research.

Currently, there is an ever-growing interest in carbon materials with increased deformation-strength, thermophysical parameters. Due to their unique physical and chemical properties, such materials have a wide range of applications in various industries. Many prospects for the use of polymer composite materials based on polyvinylidene fluoride (PVD...

The direction of the development of the Internet of things is due to the ever-increasing need for the Internet - the communicative component for the exchange of information not only among people, but with the increase in information, receiving it from certain devices. The development of technology has led to the transition to the Internet of things...

This review summarizes the current trends and developments in the field of polyvinylidene fluoride (PVDF) for use mainly as a nanogenerator. The text covers PVDF from the first steps of solution mixing, through production, to material utilization, demonstration of results, and future perspective. Specific solvents and ratios must be selected when c...

In this paper, modern ways of digitalization of the educational process are considered and analyzed. An alternative innovative solution can be a theory of inventive problem solving (TRIZ)-a methodology, taking into account the didactic principles of education (continuity, succession, accessibility, etc.). The dynamics of innovative technologies req...

This pre-print has been superseded by the published paper entitled: "Interpretation of field emission current–voltage data: Background theory and detailed simulation testing of a user-friendly webtool".

Thin films of bismuth and iron oxides were obtained by atomic layer deposition (ALD) on the surface of a flexible substrate poly(4,4′-oxydiphenylene-pyromellitimide) (Kapton) at a temperature of 250°C. The layer thickness was 50 nm. The samples were examined by secondary-ion mass spectrometry, and uniform distribution of elements in the film layer...

Hydrogen impregnation is one of the main sources of contamination in AlN thin films obtained by atomic layer deposition method (ALD) as many studies report. Such impurities can be potentially detrimental to mechanical and electrical properties of the material. In this study methods belonging to ion-beam analysis (IBA) group, namely: elastic recoil...

Thermal treatment conditions of solid polymer polymer electrolyte (SPE) were studied with respect to their impact on the surface morphology, phase composition and chemical composition of an imidazolium ionic-liquid-based SPE, namely PVDF/NMP/[EMIM][TFSI] electrolyte. These investigations were done using scanning electron microscopy, Raman spectrosc...

The method of inclusion of various additives into a polymer depends highly on the material in question and the desired effect. In the case of this paper, nitride salts were introduced into polyvinylidene fluoride fibers prepared by electrospinning. The resulting changes in the structural, chemical and electrical properties of the samples were obser...

Polyvinylidene fluoride (PVDF) is one of the most promising electroactive polymers; it exhibits excellent electroactive behaviours, good biocompatibility, excellent chemical resistance, and thermal stability, rendering it an attractive material for biomedical, electronic, environmental and energy harvesting applications. This work aims to further i...

As widely-available silicon solar cells, the development of GaAs-based solar cells has been ongoing for many years. Although cells on the gallium arsenide basis today achieve the highest efficiency of all, they are not very widespread. They have particular specifications that make them attractive, especially for certain areas. Thanks to their durab...

Modern material science often makes use of polyvinylidene fluoride thin films because of various properties, like a high thermal and chemical stability, or a ferroelectric, pyroelectric and piezoelectric activity. Fibers of this polymer material are, on the other hand, much less explored due to various issues presented by the fibrous form. By intro...

This work is dedicated to the description of the degradation of GaAs solar cells under continuous laser irradiation. Constant and strong exposure of the solar cell was performed over two months. Time-dependent electrical characteristics are presented. The structure of the solar cells was studied at the first and last stages of degradation test. The...

Limitations of ceramic piezomaterials (brittleness, toxicity of lead-containing samples, difficulties of complicated shapes preparations, etc.) call for the research in the field of piezoelectric polymers. One of them is polyvinylidene fluoride (PVDF). It could be prepared in various forms: thin films, bulk samples, fibers. PVDF fibers attract the...

In this study a comparison of the topography of BiFeO 3 (BFO) thin films deposited on tantalum pentoxide substrates of different thicknesses is provided. The Ta 2 O 5 substrates had a roughness increasing with the film thickness. The relationship between substrates of different topography but the same composition with the quality of the growing bis...

Polyvinylidene fluoride (PVDF) is a modern polymer material used in a wide variety of ways. Thanks to its excellent resistance to chemical or thermal degradation and low reactivity, it finds use in biology, chemistry, and electronics as well. By enriching the polymer with an easily accessible and cheap variant of graphite, it is possible to affect...

PurposeThe morphological stability of silicon single crystal wafers was investigated, after performing cleaning surface treatments based on moderate temperature annealing and plasma sputtering.Methods The wafer surfaces were measured by Tapping mode atomic force microscopy in air, before and after the different treatments. The 3D images were segmen...

BiFeO3 (BFO) films on highly oriented pyrolytic graphite (HOPG) substrate were obtained by the atomic layer deposition (ALD) method. The oxidation of HOPG leads to the formation of bubble regions creating defective regions with active centers. Chemisorption occurs at these active sites in ALD. Additionally, carbon interacts with ozone and releases...

The aim of this study is motivated by the pursuit to investigate the performance of new and as yet untested precursors such as hydrazinium chloride (N 2 H 5 Cl) and triisobutylaluminum Al(C 4 H 9) 3 in the AlN atomic layer deposition (ALD) process as well as to study effects of successive annealing on the quality of the resulting layer. Both precur...

This paper investigates field emission behavior from a surface of a tip that was prepared from polymer graphite nanocomposites subjected to electrochemical etching. The essence of the tip preparation is to create a membrane of etchant over an electrode metal ring. The graphite rod acts here as an anode and immerses into the membrane filled with alk...

The structure and properties of gallium arsenide photovoltaic cells were investigated using a wide range of analytical methods. Solar cells were exposed to intense gamma irradiation with a dose of 500 kGy. The radioactive isotope Cobalt-60 was used as the emitter. Fourier transform infrared spectroscopy (FTIR), ellipsometry, and spectrophotometry w...

The influence of gamma irradiation on gallium arsenide based photovoltaic cells was investigated. This type of solar cell is used for advanced space application where radiation degradation occurs in particular. A synthetic radioactive isotope of cobalt Co-60 was used with an applied dose of up to 500 kGy. These irradiation cause damage and degradat...

The purpose of this work is study of silicon single crystal wafer thermal stability in correlation with three-dimensional (3D) surface characterization using atomic force microscopy (AFM). The samples were heated up to 500 °C for the period of 2 and 4 h. Then the surfaces of wafers were processed by ion beam. The difference in surface structure of...

We report on influence of the surface functionalization on the properties of highly oriented pyrolytic graphite. The samples were processed in nitric acid and characterized by XPS, Raman and EDX spectroscopies, AFM, SEM and optical microscopy. It is shown that interaction of nitric acid with the surface of HOPG leads to two types of reactions: oxid...

Graphite finds use in a large amount of nanoscale applications, including as a substrate for thin film and nanomaterial deposition. With its excellent properties for usage in nanoscale and given the regularity of structure of highly oriented pyrolytic graphite (HOPG), the possibility of use to acquire more precise and detailed results is high. To t...

This paper describes impact of micro-courses to education in the field of the nanoscience. The feature of the subjects which are related to nanoscience is the combination of new modern research methods and the foundations of physics and chemistry. While there are well-developed textbooks to study the fundamentals, it is necessary to refer to freshl...

This work aims to clarify the application of electron beam-induced current (EBIC) method for the morphological analysis and detection of local defects and impurities in semiconductor structures such as solar cells. One of the advantages of this method is to observe a leakage path and microplasma sites with nanometer resolution. This technique allow...

This study focuses on structural imperfections caused by hydrogen impurities in AlN thin films obtained using atomic layer deposition method (ALD). Currently, there is a severe lack of studies regarding the presence of hydrogen in the bulk of AlN films. Fourier-transform infrared spectroscopy (FTIR) is one of the few methods that allow detection bo...

Numerical analysis was applied to three-dimensional (3D) images for a quantitative description of evolution of surface topography of CdTe after oxidation. The results of fractal analysis show the correlation of fractal dimension and statistical characteristics of surface topography. Surface texture analysis provides dependence of topography charact...

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...

In this paper, the authors presented first results on the theoretically studying of adsorption of alkali metal cations on the surface of activated carbons with approximation of a cluster model. The evaluation of oxygen-containing carbon cluster compounds stability with cations of alkali metals has been carried out according to quantum chemical calc...