Creation Of New Functional Materials Research Articles

Selective 3-dimensional patterning during phase separation of a continuously laminated layer

Control over the physical properties of materials is ubiquitously required in many fields. One means by which this can be achieved is controlling the internal structure of multi-component materials with an eye to enhancing mechanical properties. Here, we focus on self-organized pattern formation in phase separating materials, where microscopic patterns with a smooth, continuous connection may be realized. We propose a feasible method to control pattern formation using phase separation combined with continuous ``lamination'' of material, when material is continuously and homogeneously layered on top of a base. We find that a random droplet pattern, a lamellar pattern, and a cylindrical pattern are formed depending on the lamination rate $V$. We clarify the dynamics of pattern formation, focusing on the mechanism. This study may lead to the creation of new functional materials through artificial pattern control.

Mechanochemical Activation of Superradiance in Paramagnetic Polymer Composites.

The review examines the effect of radio-frequency superradiance during pulsed mechanochemical activation of polymer composites under high pressure. Mechanochemical activation is implemented in three modes: (a) rheological explosion of polymer composite under rapid uniaxial compression, when an elastic wave pulse occurs in a polymer composite sample and implements the physico-chemical transformations leading to the occurrence of a superradiance pulse; (b) parametric mode, when an elastic wave pulse is introduced from the outside through a waveguide into a composite sample; (c) the mode of rapid pressure release, which also leads to the occurrence of a superradiance pulse. Paramagnetic polymer composites-namely polystyrene-binuclear clusters Co(QH)2-O-Co(QH)2 or Mn(QH)2-O-Mn(QH)2, where QH is a ligand based on QH2-3,6-di-tert-butylpyrocatechin)-are considered as objects implementing such processes. These binuclear clusters exhibit the Dzyaloshinskii-Moriya effect, and polymer composites based on them exhibit multiferroic properties. A composite of a molecular magnet in polystyrene matrix (Eu(III)(SQ)3·bipy complex with four unpaired electrons on Eu(III) and on SQ ligands; SQ is 3,6-di-tert-butylquinolate paramagnetic ligand) is also considered. The binuclear clusters and europium complexes form 2D nano-objects in the polymer matrix with a diameter of 50-100 nm and a thickness of ~ 1-2 nm. The review considers the formalisms of Dicke, Lorentz, Landau-Lifshitz-Blombergen and Havriliak-Negami equations, which make it possible to conduct a time-frequency analysis of these processes, to obtain data on the relaxation processes of spin and charge density in objects responsible for the process of radio-frequency superradiation. It is also shown that the analysis of electron spin resonance data allows us to provide a probable quantum chemical scheme for the implementation of the radio-frequency superradiance process. The phenomenon of superradiation has a great deal of potential in such areas as energy-saving technologies, wireless power transmission and storage devices. The technique of studying fast mechanochemical processes considered in the review allows us to investigate the mechanisms of interaction of magnetic and electrical subsystems in multiferroics and molecular magnets, which expands the scientific base for the creation of new functional materials and enables the solving of related problems of condensed matter physics.

Recent advances in piezoelectric textile materials: A brief literature review

Smart textiles (ST) can be defined as materials capable of detecting an external stimulus, responding, and adapting its behavior according to the stimulus obtained. The field of study and development of these materials is extensive, and ST can be seen in areas such as health, transport, security, civil construction, and sports. Piezoelectric textiles are part of the ST category and are characterized due the ability to generate electrical energy from mechanical stimulus, and vice versa. Therefore, the main objective of this review is to present the current research on piezoelectric ST. In addition, the study highlights the process of obtaining materials with piezoelectric properties and the challenges and limitations, seeking to understand the contribution of the development of these materials in the field of wearable electronic devices. Thus, the main challenge in developing piezoelectric textiles is in the ability to supply energy to electronic devices to be applied in various fields such as motion detection, acoustics, impact absorption, among others. Moreover, piezoelectric ST is remarkably promising for the development of wearable electronic textiles (e-textiles) that consequently impact the creation of new functional materials that enable renewable sources to offer a positive contribution in the daily society.

Magnetic Semiconductors as Materials for Spintronics

From the various aspects of spintronics the review highlights the area devoted to the creation of new functional materials based on magnetic semiconductors and demonstrates both the main physical phenomena involved and the technical possibilities of creating various devices: maser, p-n diode with colossal magnetoresistance, spin valve, magnetic lens, optical modulators, spin wave amplifier, etc. Particular attention is paid to promising research directions such as ultrafast spin transport and THz spectroscopy of magnetic semiconductors. Special care has been taken to include a brief theoretical background and experimental results for the new spintronics approach employing magnetostrictive semiconductors—strain-magnetooptics. Finally, it presents top-down approaches for magnetic semiconductors. The mechano-physical methods of obtaining and features of the physical properties of high-density nanoceramics based on complex magnetic oxides are considered. The potential possibility of using these nanoceramics as an absorber of solar energy, as well as in modulators of electromagnetic radiation, is shown.

(Digital Presentation) Development of an Eam-Type Interatomic Potential Model Reproducing Theoretical Energetics in Polytype Structures

The allotropes composed of close-packed (CP) structures that differ only in the stacking order in the system are called the CP polytypes [1]. The CP polytype is also considered one of the physical systems realizing the Kepler conjecture [2]. Since the significant changes in physical properties due to the intentional polytype formation have been reported in various fields of metallic and semiconductive systems [3-5], the material engineering demand for polytype phase control is diverse. The acquisition and deepening of scientific knowledge for the polytype phase control is therefore promising to lead to the creation of new functional materials. However, the scientific control of the polytype stacking order is still incomplete in the field of practical materials engineering. This is because the polytype control technology has many uncertainties since the formation mechanism of polytype is physically unsolved yet. Predicting polytype phase stability for a material has also been a long-standing issue in condensed matter physics and/or materials science. This situation stems from the fact that the atomistic interactions on polytype energetics might be surprisingly quite complex and delicate despite the simplicity of their geometrical structure. In the previous paper, we have presented an analytical theory on the total energetics for the CP polytypes based on the geometrical analysis for the correlation between interlayer interactions and interatomic ones in CP polytypes [6]. Our theoretical studies have shown that the long-range nature of interatomic interactions is an important factor for reproducing the static polytype energetics [6,7]. Based on our theory submitted [6], we have tried to construct an EAM (Embedded Atom Method) [8] type interatomic model for metallic La reproducing the theoretical polytype energetics. Our primary motivation for the present study is to grasp why long periodic polytype structures other than 2H and 3C ones appear as the stable phase under the crystal growth for the specific elemental systems. Therefore, we aim to develop the interatomic potential to reproduce the theoretical polytype energetics and to adopt it to the dynamical simulations for the long-periodic polytypes systems. The ground state for La is the 4H structure which is the simplest long-periodic polytype and La can exist in both 4H phase and the 3C phase under 583K [9]. Thus, it is possible to investigate the essential factors determining the polytype selection rule through the atomistic dynamics for metallic La. From our research so far, we have succeeded in constructing an EAM-type potential that mimics the energetics of metallic La with the 4H as the ground structure [10]. The following three procedures are found to be essentially important for deriving an interatomic interaction model with the 4H structure as the ground state; (i) The cutoff radius should be set to have a relatively longer distance (three or more interlayer distances in the 4H stacking structure). (ii) The equations of state (EOS) for the energetics of 2H, 3C, and 4H structures need to be reproduced as accurately as possible. (iii) The adiabatic potential along important transition paths between crystal structures such as the Bain path for the bcc-fcc transition must be exactly considered [11]. These procedures have made the interaction model describable for not only the energetics but also the lattice dynamics such as dynamical instability, which is known to be generally significant for the phase transition phenomena [11, 12]. The transferability of the associated potential and some results adapted in the molecular dynamics (MD) simulations will be also discussed in the presentation of the day.[1] A. L.Ortiz et al., J. Appl. Cryst. 46, 242 (2013).[2] T. Hales et al., Forum of Mathematics, Pi, 5, E2 (2017).[3] R. Yakimova et al., J. Cryst. Grow. 217, 255 (2000).[4] Z. Fan et al., Nat. Commun. 6, 7684 (2015).[5] E. M. T. Fadaly et al., Nature. 580, 205 (2020).[6] S. Ogane and K. Moriguchi, MRS Advances 6, 170 (2021).[7] K. Moriguchi et al., MRS Advances 6, 163 (2021).[8] Murray S. Daw and M. I. Baskes, Phys. Rev. B 29, 6443 (1984).[9] B. Love, “Metal Handbook”, Vol. 1, American Society for Metals, Novelty, Ohio, 1961, pp 1230-1231.[10] S. Ogane, et al., 2021 MRS Fall Meeting & Exhibit, CH02.13.05 (2021).[11] K Moriguchi and M Igarashi, Phys. Rev. B 74, 024111 (2006).[12] G. Grimvall et al., Rev. Mod. Phys. 84, 945 (2012).[13] S. Baci et al., Phys. Rev. B 81 (2010) 144507. Figure 1

Synthesis of nanostructured protein-mineral-microcapsules by sonication.

We propose a simple and eco-friendly method for the formation of composite protein-mineral-microcapsules induced by ultrasound treatment. Protein- and nanoparticle-stabilized oil-in-water (O/W) emulsions loaded with different oils are prepared using high-intensity ultrasound. The formation of thin composite mineral proteinaceous shells is realized with various types of nanoparticles, which are pre-modified with Bovine Serum Albumin (BSA) and subsequently characterized by EDX, TGA, zeta potential measurements and Raman spectroscopy. Cryo-SEM and EDX mapping visualizations show the homogeneous distribution of the densely packed nanoparticles in the capsule shell. In contrast to the results reported in our previous paper,1 the shell of those nanostructured composite microcapsules is not cross-linked by the intermolecular disulfide bonds between BSA molecules. Instead, a Pickering-Emulsion formation takes place because of the amphiphilicity-driven spontaneous attachment of the BSA-modified nanoparticles at the oil/water interface. Using colloidal particles for the formation of the shell of the microcapsules, in our case silica, hydroxyapatite and calcium carbonate nanoparticles, is promising for the creation of new functional materials. The nanoparticulate building blocks of the composite shell with different chemical, physical or morphological properties can contribute to additional, sometimes even multiple, features of the resulting capsules. Microcapsules with shells of densely packed nanoparticles could find interesting applications in pharmaceutical science, cosmetics or in food technology.

Discovery of single gyroid structure in self-assembly of block copolymer with inorganic precursors

Triply periodic hyperbolic surfaces have attracted great attention due to their unique geometries and physical properties. Among them, the single gyroid (SG) is of significant interest due to its inherent chirality as well as the potential applications in energy and environmental science. However, the formation of the thermodynamically unstable structure is still unclear. In this work, we show the formation of SG structure in the structural transformation from the cylindrical to shifted double diamond (SDD) scaffold in a self-assembly system of diblock copolymer and silica precursors in solution. It has been found that the cylindrical tubes with zero Gaussian curvature were split and curved into hyperbolic surfaces and extruded to form SG structures and further evolved into the SDD networks. This growth or extrusion process suggests the SG structure is an intermediate phase of the cylindrical and SDD, and this transformation is found similar to the formation of butterfly wing scales (Thecla opisena), which has not been observed in neither the theoretical calculation nor the experimental self-assembly of amphiphilic molecules. We hope the structural relationship may bring new insights in understanding the formation of single networks in the biological system and the creation of new functional materials.

Concerted Photoluminescence of Electrochemically Self-Assembled CuSCN / Stilbazolium Dye Hybrid Thin Films

Whether they are inorganic or organic, the key words for creation of new functional materials should be (1) solution, (2) low temperature, and (3) rare-element-free for sustainable development. As a leading example, we explore electrochemical self-assembly (ESA) of inorganic / organic hybrid thin films. In addition to the interests to study evolution of unique hybrid structures, concerted new functionalities are anticipated due to intimate interaction between the inorganic and organic constituents. Herein, we report ESA of CuSCN / 4-(N,N-dimethylamino)-4’-(N’-methyl)stilbazolium (DAS) hybrid thin films and its concerted photoluminescence (PL) behavior [1]. Hybrid thin films of crystalline CuSCN/DAS in three distinctively different nanostructures were obtained by ESA from a single pot containing all the chemical ingredients. Adsorption of DAS during the electrochemical precipitation of CuSCN result in significant change of film morphology, crystal structure and its orientation, as DAS “occluded” into crystal grains of β-CuSCN, DAS phase separated nano-“haircomb” shape β-CuSCN, and DAS phase-separated in nano-“scale” shape α-CuSCN, by simply increasing DAST concentration in the bath [2]. Their optical properties for UV-vis-NIR absorption, photoluminescence (PL), and PL excitation (PLE) spectra were examined between 77 and 298 K, in comparison with solution and solid powder of DAS tosylate (DAST). While all the fluorescent dyes we previously found to hybridize with CuSCN underwent quenching due to hole injection from dye excited state to the valence band of CuSCN, DAS presented the first and only example to exhibit PL when combined with CuSCN [3]. DAST exhibited a strong exciton-phonon coupling to weaken, broaden, and red shift PL at room temperature, so that it inversely is strongly enhanced, sharpened, and blue-shifted at 77 K. However, the PL of the same dye in the hybrid thin film shows a slight red shift and not much intensified. Dielectric environment as well as ordered alignment of DAS greatly stabilize exciton against thermalization loss by suppressing twisted intramolecular charge transfer (TICT) and exciton-phonon coupling. The smallest temperature dependence, thus to be interpreted as the strongest exciton stabilization, was found for the “haircomb” β-CuSCN/DAS hybrid. The PLE spectra of the “scale” α-CuSCN/DAS hybrid show a prominent sharp peak at 380 nm and another double-peak between 400 and 450 nm by cooling temperature. The former corresponds to the band-edge absorption of CuSCN, while the latter being similar to the LMCT absorption of [Cu(SCN)]+ complex. It has been confirmed that those peaks in PLE spectra indicate the contribution of CuSCN thin film without DAS for the generation of PL. These contributions of the light absorption by CuSCN to the PL from DAS clearly indicate energy transfer from CuSCN to DAS as a concerted PL mechanism. Concerted PL by energy transfer from CuSCN to DAS has also been found to occur efficiently, especially for the “scale” α-CuSCN/DAS with the largest contact area due to interpenetrating hybrid nanostructure in the smallest domain size. Those hybrid thin film having the concerted PL mechanism (Fig. 1) can possibly make these materials useful as LEDs.[1] K. Uda et al., ACS Omega, 2019, 4 (2), 4056-4062.[2] Y. Tsuda et al., Chem., 2017, 148, 845-854.[3] K. Uda et al., ECS Trans., 2019, 88, 323-333. Figure 1

Синтез и структура керамики бизамещенного гексаферрита M-типа BaFe(11,5-x)Ti0,5AlxO19

The development of scientific and technological progress is impossible without the creation of new functional materials. One of the classes of such materials are hexagonal ferrites. Their unique physical properties make them an irreplaceable material for the production of high-frequency electronics. The widespread introduction of high-frequency electronics into everyday life, over the past decade, has generated great interest in hexagonal ferrites. The number of publications devoted to the synthesis of mono- and bisubstituted ferrites noticeably increases every year. Modification of the chemical composition of a ferrite by replacing some of the iron atoms with another element, without changing its structure, leads to a change in physical properties of the material. Variation of the final ferrite properties, by changing its chemical composition, is of interest and is promising for fine tuning the material properties for a specific task. The aim of the present work is to experimentally study the possibility of synthesizing ferrite with a magnetoplumbite structure, in which the iron atoms are partially replaced by the Al and Ti atoms. A review of the scientific literature on this issue showed the absence of publications on ferrites with such a set of substitute elements. The X-ray phase and structural analysis, electron microscopy, and energy-dispersive X-ray spectroscopy were used as research methods in the present study. The article offers the results of an experimental study of the possibility of obtaining bisubstituted M-type ferrite of the BaFe(11.5-x)Ti0.5AlxO19 composition, where x (Al) = 0.1, 0.5, 1. Solid-phase synthesis has been used as a method for preparing samples. This method is devoid of technological difficulties and is promising from the point of view of its scaling for the synthesis of ferrite. The samples have been sintered at three different temperatures: 1300, 1350, and 1400 °C. It is shown that in the temperature range 1300–1400 ° C the formation of monophase samples occurs. The calculation of the parameters of the crystal lattice has been made. The influence of temperature and concentration of a substituting element on the change in the parameters of the crystal lattice of the material has been revealed. The study by the electron microscopy method made it possible to reveal the presence of latent microporosity of the samples.

ОЦЕНКА РИСКОВ ПРИ ОПТИМИЗАЦИИ СОСТАВА РАДИОПОГЛОЩАЮЩИХ ДИСПЕРСНО-НАПОЛНЕННЫХ ПОЛИМЕРНЫХ КОМПОЗИЦИОННЫХ МАТЕРИАЛОВ

The problem of improving the quality of protection against electromagnetic radiation of electronic control units of aircraft is inextricably linked with the level of used materials, which is determined by their functional properties. Such materials can be radio-absorbing dispersed filled polymer composite materials (RADFPCM), to reduce the cost of creating which is relevant to develop a system for predicting the quality of RADFPCM. The subject of the research is RADFPCM. The purpose of the present research is to develop an algorithm for selecting the optimal composition of RADFPCM. The methodology for conducting the study includes theories of multi-criteria optimization and decision-making. To confirm the basic provisions of the developed algorithm for selecting the optimal composition of RADFPCM, studies were carried out on the example of a polymer composite material based on the rubber of the type SKTN grade A, powder fillers of two types and a PMS-50 (silicone fluid) additive. It is as a result established that for receiving the new filled polymer composite material which is radio-absorbing disperse filled with the value of Shore hard ness of 88.88 conventional units, the tensile strength of 91,9·104 Pa, tensile elongation of 54.42% the following structure of components is necessary: silicone SKTN grade A rubber (matrix) — 25%, iron ox ide (powder filler) — 38%, aluminum hydroxide (powder filler) — 37%, additive PMS-50–0. The proposed algorithm of selection of the optimal composition of RADFPCM can be applied in the creation of new functional materials for the aerospace industry. The developed algorithm contains a risk assessment unit according to Savage's criterion, which reduces the risk of approval of the non-optimal composition of the polymer composite material. Thus, even at the stage of computer modeling, a decision can be made on the composition of a new functional material, which reduces the cost of its creation and allows to ensure the required quality, reliability, and safety of the products for which the created materials are intended.

Photoresponsive Polymers on the Move

Photoresponsive polymers have found widespread applications for non-linear optics and solubility switching. In two recent issues of Nature Chemistry and Nature , Wu and colleagues and Broer and colleagues, respectively, introduce the next generation of photoresponsive polymers, whose mechanical properties can be switched for the creation of new functional materials that can be transformed into viscous polymer melt or self-propel under light irradiation.

Relationships between geometrical and electronic structures and optical properties of 1,8-naphthosultam substituents and derivatives: TDDFT study

Geometrical and electronic structure and optical properties of several substituents and derivatives of 1,8-naphthosultam are studied by quantum-chemical DFT and TDDFT. It is found that the substituents –NO2, –CF3, and –N(CH3)2 affect the geometrical and electronic structure the most. It is shown that the Stokes shift is greatest (≈260 nm) for compounds with the strong donor substituent –N(CH3)2, while strong acceptor substituents provide a quite small Stokes shift. The dependence of the Stokes shift on the difference in energies of the frontier orbitals of the ground and excited states of molecules is found. Of the 1,8-naphthosultam substituents considered, compounds with –N(CH3)2 substituent, which emit in the biological window region, can be advised for use in optical bioimaging. The results can be used as a basis for the development and creation of new functional materials and biologically active compounds.

Modification of cellulose as a promising direction in the design of new materials

The published data on the chemical and physical modifications of cellulose aimed at creation of a wide variety of new innovative materials for hi-tech and priority directions in the development of science and engineering are summarized. Investigations into the chemical modification of cellulose via nucleophilic substitution, regioselective insertion of functional groups, graft copolymerization, oxidation, and esterification are covered. The importance of studies dealing with the search for new solvents of cellulose aimed at extension of the potential inherent in its modification and processing and in the design of nanocellulose-based materials is emphasized. On the basis of analysis of the literature data, the potential for creation of new functional materials for biomedical investigations, medicine, and electronics is shown.

新規機能性素材の創生に役立つπ電子系化合物 —光と色で世界を変える

新規機能性素材の創生に役立つπ電子系化合物 —光と色で世界を変える

Creation of New Functional Materials – a Synthesis of Solid-State Physics and Metallurgy

Creation of New Functional Materials – a Synthesis of Solid-State Physics and Metallurgy