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[en] In connection with the development of nanotechnology in the last 15—20 years, the method of molecular layering (ML), created in the middle of the last century in the USSR, has attracted increasing attention. The features of structural-dimensional effects in the products obtained by new chemical nanotechnology and promising directions of their practical application in "core—nanoshell" compositions are considered in the review. In accordance with the synthetic capabilities of the ML method, the functional properties of the "core—nanoshell" type materials are affected by the "monolayer effect" and the substrate shielding effect, as well as the multicomponent nature of the system, and mutual structural coordination effect of the substrate and the build-up nanolayer. The review presents theoretical and experimental data on the application of the observed effects in the creation of shell pigments and fillers, modified sorbents, catalytic membrane reactors, nanodoped ceramic materials, polymers, quartz fibers with adjustable optical characteristics, electrets, etc.
[en] A significant laser-induced piezooptical response in novel CdCl0.5J 0.5 nanolayers is obtained under the influence of laser illumination. The maximal piezo-optic response is observed for off-diagonal piezooptical tensor components. The layered structure allowed to obtain the thin specimens of thickness up to 1 nm with mirror-like surfaces. The observed studies show huge dependence of the piezooptics on the nanolayer thickness and the photoinduced beam power density. The effect is completely reversible. This fact allows proposing a new type of nanomaterials, which have significant benefits with respect to the other types of piezooptical materials (i.e. a possibility to use them in the laser operated devices). (paper)
[en] In the book of abstracts there are the theses of the IX Annual conference of Nanotechnological Society of Russia which took place on the 05.04.2018 in Moscow. The consideration is given to the nanostructured metals and alloys and coatings on their base, nanocomposite polymers. The questions of nanotechnologies use in microelectronics, instrument engineering, fuel-and-energy complex as well as in biotechnology are also discussed
[ru]В сборнике представлены тезисы IX ежегодной конференции Нанотехнологического общества России, проходившей 05.04.2018 в Москве. Рассмотрены наноструктурированные металлы и сплавы и покрытия на их основе, нанокомпозитные полимеры. Обсуждаются вопросы использования нанотехнологий в микроэлектронике, приборостроении, топливно-энергетическом комплексе, а также в биотехнологии
[en] The functionalization of fine primary particles by atomic layer deposition (particle ALD) provides for nearly perfect nanothick films to be deposited conformally on both external and internal particle surfaces, including nanoparticle surfaces. Film thickness is easily controlled from several angstroms to nanometers by the number of self-limiting surface reactions that are carried out sequentially. Films can be continuous or semi-continuous. This review starts with a short early history of particle ALD. The discussion includes agitated reactor processing, both atomic and molecular layer deposition (MLD), coating of both inorganic and polymer particles, nanoparticles, and nanotubes. A number of applications are presented, and a path forward, including likely near-term commercial products, is given.
[en] Full text: Covalent organic frameworks (COFs) are polymer assemblies with high crystallinity, high porosity and configurable skeletal structure. They have potential applications in filtration, gas storage, and electronic devices among others. However, the realization of these applications requires a high degree of morphological control in their preparation, and permanent high crystallinity – bonds in these frameworks are easily reversed in humid atmospheres. The construction of substrate-confined COF materials that are simultaneously highly crystalline, well-oriented and functional remains a challenge due to insufficient understanding of the basic mechanisms controlling the nucleation and growth of covalent organic frameworks, particularly on a substrate. This knowledge is crucial to further progress the development of more concrete techniques that will ultimately lead to covalent organic frameworks that are crystallographically and structurally well-defined in film form. In this poster, I will describe some of our recent progress towards synthesizing dense, crystalline COF layers. (author)
[en] Growing demand for efficient, high-resolution surface processing has led to the emergence of a rich variety of plasma-based technologies underpinned by an equally wide range of technological setups, each optimized for a specific task, e.g. highly-selective removal of surface layers, precision surface functionalization and nanoscale structuring, or deposition of thin films and nanostructures. However, with increasing device integration and miniaturization, flexible processing technologies capable of delivering complex treatments, such as the growth of complex hierarchical single- and multi-component nanostructures within a single processing environment are highly desired. Yet, such systems are difficult to achieve due to the necessity of the in-process float, and limiting technological capabilities of individual plasma sources and treatment setups. Using a novel flexible platform as an example, this review presents a careful analysis of the physical principles, capabilities and limitations of existing plasma technologies with an ultimate aim to define key principles for the development of prospective flexible platforms for complex plasma-enabled material synthesis and processing. Such a platform would have a significant potential to increase the effectiveness of plasma technology with respect to productivity, material and energy consumption, cost and turnaround time.
[en] Highlights: • Shear horizontal wave dispersion in nanolayers with surface effects is examined. • Wave velocity is dependent on the layer thickness and surface elastic constants. • Surface elastic constants can be analytically derived from the wave velocity. - Abstract: In this work, the shear horizontal (SH) wave dispersion in two dissimilar nanolayers is investigated by using the surface elasticity theory in which the surface effects are featured by surface elastic constants. It is found that the SH wave dispersion shows distinct dependence on the nanolayer thickness as well as the surface elastic constants. The larger the surface elastic modulus and/or the smaller the thickness, the higher the phase velocity. In particular, as the wave frequency approaches zero, the analytical relation between the phase velocity in the first mode dispersion and the surface elastic constants is deduced. Thereby, a facile method is suggested to determine the surface elastic constants from the phase velocity of SH waves scattered in nanolayers.
[en] Full text: The properties of 2D materials are sensitive to structural defects. Controlling the nature and concentration of defects therefore provides a means of tailoring material properties for specific applications. Ion irradiation is a well-established technique that provides a practical means of defect engineering, so there is particular value in understanding how the structure and concentration of defects depend on ion-irradiation parameters. This study examines the effect of several important aspects of ion-induced radiation damage in graphene, namely: the effect of the ion fluence and nuclear stopping power (Sn) of incident ions on the concentration and structure of defects; the role of the substrate in damage production; and the significance of collective effects associated with molecular ion irradiation. (author)
[en] Active triggering and manipulation of ultrafast flux dynamics in superconductors are demonstrated in films of Nb. Controlled amounts of magnetic flux were injected from a point along the edge of a square sample, which at 2.5 K responds by nucleation of a thermomagnetic avalanche. Magneto-optical imaging was used to show that when such films are cooled in the presence of in-plane magnetic fields they become anisotropic, and the morphology of the avalanches changes systematically, both with the direction and magnitude of the field. The images reveal that the avalanching dendrites consistently bend towards the direction perpendicular to that of the in-plane field. The effect increases with the field magnitude, and at 1.5 kOe the triggered avalanche becomes quenched at the nucleation stage. The experimental results are explained based on a theoretical model for thermomagnetic avalanche nucleation in superconducting films, and by assuming that the frozen-in flux generates in-plane anisotropy in the film thermal conductance. The results demonstrate that applying in-plane magnetic fields to film superconductors can be a versatile external tool for controlling their ultrafast flux dynamics. (paper)
[en] Highlights: • Well-tailored interlocked interfaces were fabricated through a cost-effective process such as nanoscale molding and electrodeposition. • It was predicted that well-tailored interlocked interfaces is possible to maximize the output power due to the increment of contact area from simulation. • Triboelectric nanogenerator with well-tailored interlocked interface exhibited the highest output power compared with 3 different types of interfaces. • For charging and discharging of capacitor, triboelectric nanogenerator with well-tailored interlocked interfaces showed the superior characteristics compared to that with smooth interface. We report a facile and cost-effective route for fabricating highly efficient triboelectric energy harvesters via formation of artificially well-tailored interlocked interface with a nanostructured Ni electrode and polydimethylsiloxane (PDMS). The interlocked interface formed between the nano-pillar Ni electrode and nano-pillar PDMS composite thin film effectively enhanced the triboelectricity of a triboelectric nanogenerator (TENG) by increasing the surface contact area and contact time, related to the frictional forces. The output power of four different kinds of TENGs was evaluated to confirm the effect of the surface morphology, especially the interlocked interface. A dramatic enhancement of the output voltage (~100 V) was observed with a current of up to ~23 μA. The effectiveness of the interlocked TENG (i-TENG) was also demonstrated by the greater efficiency for charging a capacitor compared with the flat-to-flat contact TENG (flat TENG).