The phosphating process has been devoted to optimizing the electrochemical performance of vanadium oxide electrode for zinc-ion batteries. The NH₄V₄O₁₀ is modified by the interlayer phosphate groups and oxygen defects （P-NVO-2） through phosphating, which provide the electrode material with a stable structure, large interlayer spacing, and high conductivity. The phosphate groups and oxygen vacancies widen the interlayer spacing, cause lattice distortion and provide shortcuts for electrolytes, conducing to the ion diffusion kinetics. The phosphate groups immobilize the interlayer intrinsic ammonium ions and prevent the irreversible phase transition of P-NVO-2 during the cycle. Combined with the kinetics analysis, appropriate phosphate groups and oxygen defects reduce the migration barrier, improve the electronic conductivity and afford extra electrons. Besides, it is found that the cathode after phosphating exhibit intercalation pseudocapacitive behavior, thus resulting in superior performance. Therefore, P-NVO-2 electrode delivers an outstanding specific capacity of 433.7 mAh g^-1 at 0.5 A g^-1, excellent rate performance of 300.9 mAh g^-1 at 10 A g^-1, and high capacity retention of 95.1% after 7000 cycles at 10 A g^-1. In addition, P-NVO-2 also exhibits brilliant electrochemical performance when applied to the flexible soft-packaged battery, confirming the application potential. Therefore, the exploration of P-NVO-2 material with appropriate phosphate and oxygen vacancies supply a prospective approach for designing high-rate and long-cyclicality zinc-ion batteries.

The absorption spectra of Ketoprofen in the UV domain was plotted using absolute methanol p.a. as a control solvent. The maximum absorption wavelength was determined to be at λ = 254 nm for a ketoprofen solution of 1,4 µg /mL prepared from pure crystalline standard ketoprofen dissolved in methanol p.a. The applied method was the subject of a statistical validation procedure, which consisted in completion of the following stages: the linearity of the method studied over the entire chosen concentration range 2.0 μg / mL - 80.0 μg / mL; detection limit (LD), quantitation limit (LQ), Sandell’s sensitivity, interference of the excipients, stability of prepared standard solutions, method and system precision and accuracy of this method. All statistical parameters were within the normal limits. This analysis method has been statistically validated and can be used anytime and anywhere for UV Ketoprofen spectrophotometric assay in a wide range of samples. The amount of pure ketoprofen assigned on the pharmaceutical tablet was found to be 146.326 mg ketoprofen / tablet. This value was very close to the official declared content of the active substance (150 mg pure ketoprofen/ tablet) set by the official pharmaceutical company, with an average percentage deviation of only 2,45% from the official declared pure content . This calculated value (2,45%) was situated below the maximum percentage error from the official content. of declared active substance (± 5%) imposed by official Pharmacopoeias. So, the pharmaceutical product fully respects the normal official limits provided by the Romanian Pharmacopoeia, 10th Edition and also by the European and International Pharmacopoeias rules.

The mechanical properties extraction of the ultrathin film is a big challenge to be determined and controlled. In this study, we select a non-contact method to conduct the measurement of the TaN ultrathin film, which can effectively prevent to damage the TaN film at the same time. Firstly, we exploit the PVD process with various gas ratios to deposit the TaN thin film on the SiO₂ cantilevers. Then, we analyze the mechanical properties of the TaN thin film to extract the major characteristics. The frequency and geometry would dominate the performance of Young’s modulus.

On the other hand, residual stress is accumulated by all the random stress induced during the process. Especially, uniform stress has a major impact on residual stress. Therefore, the uniform stress can be simplified as the residual stress and also can be expressed by the Stoney equation.

According to our experimental results, the N₂ gas ratios-dependent Young’s modulus of TaN thin film is located at approximately 247.55±6.11GPa. In addition, the residual stress is reduced from -1.02GPa to -0.74GPa as the N₂ flow increases. Consequently, we provide an efficient approach to modifying the mechanical properties of ultrathin TaN film and the N₂ gas ratios can validate its mechanical properties during the deposition process.

Nanobiotechnology is a broad science that provides nanomaterials to solve many medical, agricultural, engineering, biological and chemical problems. Metallic nanoparticles are the kind of nanomaterials with zero dimensions. Nowadays, the synthesis of semiconductor nanoparticles has received much attention due to its many applications in various scientific fields. In general, nanoparticles can be synthesized by three physical, chemical and biological methods. In this study, ZnO-NPs were synthesized using biological method. In the biological method, the aqueous extract of Juglans regia green husk was used as an agricultural waste material to produce nanoparticles. Therefore, in this research, nanoparticles were synthesized by the green method and their chemical and physical properties were determined. The properties of the synthesized nanoparticles were investigated by UV-Visible spectroscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS) and transmission electron microscopy (TEM). The results of UV-Vis analysis showed that the biosynthesized zinc oxide nanoparticles have a strong SPR band at 360 nm. XRD analysis showed that these nanoparticles are crystalline in nature and FTIR revealed the capping agent of these nanoparticles. Also, the results of DLS analysis showed that the hydrodynamic diameter of 90% of the biosynthesized zinc oxide is less than 292.55 nm. Furthermore, TEM analysis confirmed that these nanoparticles have spherical and ellipsoidal shapes.

In this experiment, an inner transition metal oxide-based nanocomposite of ferrite and antimony heterojunction (LaFeO₃/Sb₂O₃) was fabricated by hydrothermal method for photocatalytic degradation of malachite green (MG) dye under the irradiation of visible light. The fabricated nanocomposite was characterized by various analytical techniques such as Fourier Transform Infrared Spectroscopy (FTIR) for functional group analysis, X-ray diffraction (XRD) plan determines the nanocomposite crystalline size the typical crystalline size of around 42 nm was calculated via the Debey -Scherrer method, and Field emission scanning electron microscopy (FE-SEM) determines overall morphology of the composite depicts the random distribution of Sb particles over Ln, which has led to increased reactive sites and probably may result in increased surface area. UV−Vis absorption spectra confirmed an absorption peak at 420 nm in the visible region, and band gap values are found to fall in the range of 2.4 eV. The energy dispersive X-ray (EDAX) analysis confirmed the presence of Ln and Sb in the sample. Moreover, the surface areas of the prepared samples were determined by the electrochemical double-layer capacitance (EDLC) using cyclic voltammetry. Impedance studies demonstrated lower charge transfer resistance for the heterojunction as compared to ferrite and antimony oxide. The photocatalytic activity of the samples was checked for the decolorization of malachite green and it was observed that the composite nanomaterials show maximum response with 95% degradation of MG in a period of 88 minutes. Scavenging experiments established the involvement of hydroxyl radicals (OH˙) in the photodegradation mechanism of malachite green while recycling experiments demonstrated the reliability and long-term use of the catalysts.

Single-walled carbon nanotubes (SWCNTs) are very important material for many applications. The chemical functionalization of carbon nanotubes such as covalent, noncovalent modifications, substitution of carbon atoms in walls, intercalation, filling allow modifying precisely the properties of carbon nanotubes. Here I perform the filling of SWCNTs with gallium selenide [1], lead halogenides [2], and rubidium iodide [3], and investigate the properties with Raman spectroscopy, near edge X-ray absorption fine structure spectroscopy, photoemission spectroscopy, optical absorption spectroscopy [4]. It is shown that the introduced salt leads to the modification of the electronic properties of carbon nanotubes [5]. The p-doping is observed. The successful filling of carbon nanotubes with high filling ratio and high doping level of SWCNTs can find applications in different fields.

[1] M. V. Kharlamova. Novel approach to tailoring the electronic properties of single-walled carbon nanotubes by the encapsulation of high-melting gallium selenide using a single-step process, JETP letters, 2013, V. 98, № 5, p. 272-277

[2] M. V. Kharlamova, C. Kramberger, P. Rudatis, T. Pichler, D. Eder. Revealing the doping effect of encapsulated lead halogenides on single‑walled carbon nanotubes, Appled Physics A, 2019, V. 125, article number 320

[3] M. V. Kharlamova, C. Kramberger, P. Rudatis, K. Yanagi, D. Eder. Characterization of the electronic properties of single-walled carbon nanotubes filled with an electron donor - rubidium iodide: multifrequency Raman and X-ray photoelectron spectroscopy studies, Physica Status Solidi B, 2019, V. 256, № 12, article number 1900209

[4] M. V. Kharlamova, C. Kramberger. Spectroscopy of filled single-walled carbon nanotubes. Nanomaterials 2022, 12, 42.

[5] M. V. Kharlamova. Advances in tailoring the electronic properties of single-walled carbon nanotubes, Progress in Materials Science, 2016, V. 77, p. 125-211

Kinetics of growth of carbon nanotubes is important for applications of material in construction field. Here I discuss the kinetics of growth of carbon nanotubes inside metallocene-filled single-walled carbon nanotubes (SWCNTs). The growth mechanism of carbon nanotubes is revealed [1]. It includes stages of growth on carbide and metallic catalyst particles [2]. Two stages are characterized with growth rates and activation energies [3]. They are dependent on diameter and metal type. The growth rates increase with decreasing the nanotube diameter [4]. The activation energies also depend on diameter. They also show slight dependence on chiral angle of carbon nanotube. The metal dependence is caused by different structures of catalyst particles with different diameters. These findings are very important for construction of buildings of the future.

[1] M. V. Kharlamova, C. Kramberger. Metal cluster size-dependent activation energies of growth of single-chirality single-walled carbon nanotubes inside metallocene-filled single-walled carbon nanotubes, Nanomaterials, 2021, V. 11, № 10, article number 2649

[2] M. V. Kharlamova, C. Kramberger, T. Saito, Y. Sato, K. Suenaga, T. Picher, H. Shiozawa. Chirality-dependent growth of single-wall carbon nanotubes as revealed inside nano-test tubes, Nanoscale, 2017, V. 9, № 23, p. 7998-8006

[3] M. V. Kharlamova, C. Kramberger, Y. Sato, T. Saito, K. Suenaga, T. Pichler, H. Shiozawa. Chiral vector and metal catalyst-dependent growth kinetics of single-wall carbon nanotubes, Carbon, 2018, V. 133, pp. 283-292

[4] M. V. Kharlamova, C. Kramberger, T. Saito, T. Pichler. Diameter and metal-dependent growth properties of inner tubes inside metallocene-filled single-walled carbon nanotubes, Fullerenes, Nanotubes and Carbon Nanostructures, 2020, V. 28, № 1, pp. 20-26

The development of new approaches of supramolecular chemistry and the identification of the structure–activity relationship is an important and promising problem. Macrocyclic platforms - thiacalix[4]arenes, can be used for the synthesis of compounds with a regulated ability to self-assembly. Due to the ability to fix the macrocyclic ring in several conformations and the relative ease of its functionalization, functional groups can be arranged in a predetermined manner in space. It determines the tendency to self-assembly into nanostructures under the influence of the substrate (ions, molecules).

In this work, we synthesize sulfobetaine derivatives of thiacalix[4]arene in three conformations. In the presence of Ag⁺, these derivatives are capable to self-assemble into associates with different architectures (shapes) and, as a consequence, with cytotoxic selectivity for the cervical carcinoma cell line.

The dynamic light scattering method showed that the synthesized macrocycles in cone, partial cone and 1,3-alternate conformations form submicron-sized particles with Ag⁺ in water, but the particle size and polydispersity of the systems studied depend on the macrocycle conformation. The type of coordination determines the different shapes of the associates. Cytotoxic properties are shown to be controlled by the shape of associates, with the highest activity demonstrated by thiacalix[4]arenes in partial cone conformation.

The work was supported by Russian Science Foundation (№18-73-10094), https://rscf.ru/project/18-73-10094/

pH‒Sensitive systems with fluorescent properties based on polyfunctional macrocyclic pillar[5]arene platforms represent a promising approach for designing drug delivery complexes and imaging markers. Herein, we propose and develop an approach to synthesis of pillar[5]arene derivatives with amino acids residues (L‒tryptophan and L‒phenylalanine) and obtaining fluorescein containing nanoparticles with fluorescein properties and its subsequent release depending on the pH. Fluorescein containing nanoparticles were obtained by mixing solutions of synthesized pillar[5]arenes and fluorescein. Dynamic light scattering and transmission electron microscopy were used to determine the size and shape of the obtained particles. The size of spherical nanoparticles was 79÷1 and 92÷1 nm for particles based on pillar[5]arene with L‒phenylalanine and L‒tryptophan residues respectively. The ability to form complexes and associates with fluorescein by synthesized macrocycles was studied by electron UV–vis and fluorescence spectroscopy, two–dimensional ¹H–¹H NOESY NMR spectroscopy and dynamic light scattering. Pillar[5]arene with L‒phenylalanine moieties more efficiently binds fluorescein (lgK_a = 3.92) compared with pillar[5]arene with L‒ tryptophan moieties (lgK_a = 2.94). The two systems exhibited different fluorescence mechanisms AIE for the mixed particles based on pillar[5]arene with L‒ phenylalanine residues and ACQ ‒ for pillar[5]arene with L‒ tryptophan residues. It was found that the fluorescein release was observed only from the associates based on pillar[5]arene with L‒tryptophan residues in the neutral (pH = 7.4) and alkaline (pH = 9.2) solutions. The results of this work may be useful for further research to create targeted drug delivery systems with pH‒controlled release.

The work was supported by Russian Science Foundation (№18-73-10094), https://rscf.ru/project/18-73-10094/

The rechargeable aqueous zinc ion battery (ZIB) has many advantages such as high volume specific capacity, high security, easy assembly, low cost, environmental friendliness and abundant zinc resources. However, their specific capacity is still low compared with lithium ion battery, and current academic research interesting has been focused on developing new cathode materials with high specific capacity because they have become the constraints for the applications of ZIB. A simple self-polymerization method at low temperature was used to design the Mn/V hybrid polymer backbone. During the subsequent calcination, ultrafine VN quantum dots and MnO nanoparticles were generated in situ and stably encapsulated in n-doped carbon (NC) shells to obtain a new cathode NC-VN/MnO for AZIBs. The cooperation of MnO and VN is essential for achieving long cycle lifetimes of the NC-VN/MnO cathode in two main ways. Firstly, in the initial phase, NC-VN/MnO is mainly contributed by the MnO to provide capacity, while the VN quantum dots and NC mainly improve the electrode conductivity and avoid the in situ generation of nanosheets by phase change and the dissolution of the active material. Secondly, with the slow oxidation of VN to a layered structure of vanadium oxide, more energy storage sites are exposed that can be used as charging stations for Mn-based oxides. The synergistic relay between the Mn-based and V-based oxides continues to maintain the ultra-long lifetime of ZIB. The NC-VN/MnO cathode exhibited significant long-term cycling capability, with an output capacity of 108.3 mAh g^-1 after 12000 cycles at 10 A g^-1. These results clearly and fully demonstrate the advantages of the hybrid cathode.