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Solar-to-hydrogen conversion through photocatalysis is a sustainable and promising strategy for storing solar energy. Recently, elemental red phosphorus (RP) with broad light absorption has been recognized as a potential candidate for photocatalytic hydrogen evolution, while challenges remain due to the rapid recombination of photogenerated carriers. In this work, RP modified TiO2 hollow spheres were designed and fabricated through the chemical vapor deposition method. The optimal hydrogen production rate reaching 215.5 μmol/(g h) over TiO2@RP heterostructure was obtained under simulated solar light irradiation. Experimental results evidenced that the hollow sphere structure and RP light absorber extended light absorption ability, and the heterostructure induced interfacial charge migration facilitated photoinduced charge separation, which benefited the photocatalytic hydrogen production performance.

This article is a study of the Civil Code of Ukraine as the main regulator of civil relations in civil society. The history of adoption of the Civil Code of Ukraine and its conceptual foundations were reviewed. Particular attention is paid to the problem of dualism of private law in Ukraine. The structure and content of the Civil Code of Ukraine were analysed. Attention is also paid to the main novelties of the Civil Code of Ukraine. The principal rules for the regulation of legal entities were analysed. Novelties in defining the object composition of civil legal relations are considered. Particular attention is paid to the main directions of modern scientific research in the field of the civil law of Ukraine. The study confirms the urgent need for a thorough recodification of the Ukrainian civil law, with mandatory consideration of the experience of the implementation of modern recodifications in many European countries.

The creation of carbon matrices with a high surface area for effective catalytic activity is an urgent task today, especially in the field of electrocatalysis. In this study, microporous carbon (MPS) with a surface area of about 1300 m2 g−1 was produced from raw plant waste (apricot pit shells) by successive thermal carbonation and chemical treatment. The MPS was impregnated with H2PdCl6 and calcined at various temperatures under a H2–Ar flux. The obtained Pd-NP@MPC (nanoparticle size from 1 to 25 nm) catalysts were characterized in detail by XRD, SEM, TEM and BET methods. Electrochemical tests show that the prepared composites exhibit high electrocatalytic activity and remarkable stability over time (over 50 h) for the HER process and overall water splitting performance. The electrodes have very low overpotentials (η) of 95–117 mV for HER in 1 M KOH at a current density of 100 mA cm−2. Furthermore, the Pd-NP@MPC-300 electrode can reach a high current density of 300 mA cm−2 at η merely of 170 mV and shows excellent electrocatalytic stability in prolonged water electrolysis. The relationships between MPC matrix characteristics, Pd NPs size and electrocatalytic properties are discussed in this paper.

Obtaining ceramics and composites based on cubic tungsten carbide WC1-x requires knowledge of its thermal behavior, which is poorly studied now. The paper presents the results of a thermal analysis of the nanosized WC1-x-based product with the stoichiometry of WC0.72-0.74 synthesized by a plasma dynamic method. Taking into account the known literature data on the structure of WC1-x products, an investigation of synthesized nanoparticles allows us to conclude that WC1-x cannot exist without a crystalline graphite shell and/or an amorphous carbon matrix. Similarly, the destruction of both carbon shells and a matrix leads to either quick oxidation of WC1-x to WO3 when heated in air or the phase transition WC1-x → WC when heated in vacuum. The thermal analysis shows WC1-x is stable up to 550 °C in air and up to 1200 °C in vacuum and argon. The obtained data made it possible to formulate recommendations for preserving WC1-x material in bulk specimens when compacting from the dispersed powder. The preparation of binderless ceramics from the WC1-x-based product by the SPS method seems to be impossible due to carbon diffusion during the sintering process, while the use of WC1-x-based products as a reinforcing additive to a metal (Al) matrix seems to be the only way to preserve this crystalline phase in a bulk form at the present time.

Doping with metal ions can improve the electrochemical performance of Na3V2(PO4)3 (NVP) as a cathode material for SIBs. Herein, Na3+xV2−xMIIx(PO4)3/C composites with low Co- and Cu-doping contents (x – 0, 0.01, 0.03, 0.05) have been fabricated by a facile sol–gel method. XRD, ICP-AES and XPS studies show that doping with Co2+ and Cu2+ does not alter the NVP structure of the material, and cobalt or copper successfully substitute the vanadium in its site. Raman and HRTEM data show the presence of an amorphous carbon coating on the phosphate surface, which increases the electronic conductivity of composites. Impedance spectroscopy suggests that low-level doping has significantly increased the electrical conductivity of the NVP matrix. Among all the samples of the compound, Na3.01V1.99Co0.01(PO4)3/C (capacity of 116 mA h g−1 at 0.5C) and Na3.03V1.97Cu0.03(PO4)3/C (capacity of 114 mA h g−1 at 0.5C) demonstrate the highest electrochemical ability. Moreover, even cycling at a high rate of 10C, an excellent reversible capacity is maintained at about 80% of the initial values (in the range of 72–89 mA h g−1) after 1000 cycles. The presented work analyzes the advantages of low doping and the nature of the doping metal in relation to the electrochemical properties of the NASICON-type structure, which will facilitate further commercialization of SIBs.

Стаття присвячена розгляду проблеми застосування судом способів захисту суб'єктивних цивільних прав на нерухоме майно в умовах спеціально-дозвільного типу правового регулювання діяльності суду зі здійснення правосуддя. Аналізуючи ст. 16 Цивільного кодексу України, автор звертається до проблеми numerus clausus (закритого списку) способів захисту суб'єктивних цивільних прав взагалі і суб'єктивних цивільних прав на нерухоме майно зокрема й осмислює її в контексті змін, внесених до ст. 5 Цивільного процесуального кодексу України та ст. 5 Господарського процесуального кодексу України. Автор зазначає, що діяльність суду зі здійснення правосуддя підпадає під спеціально-дозвільний тип правового регулювання, який дозволяє суду здійснювати лише ту юридичну поведінку, яка прямо визначена положеннями чинного цивільного законодавства України. У зв'язку з цим право суду визначати спосіб захисту цивільних прав, що не встановлений договором або законом, значно розширює межі судового розсуду. Водночас відповідний підхід виправданий в тих випадках, коли встановлені законом способи захисту не охоплюють всі можливі форми порушень суб'єктивних цивільних прав. При цьому суд відрізняється від інших суб'єктів правозастосування, зокрема, у зв'язку з тим, що має справу з випадками порушення суб'єктивних цивільних прав, що виходять за межі регулятивних моделей суспільних відносин. Порушення якраз і полягає в тому, що певною мірою воно має атиповий характер, не вкладається в запроваджену модель, є відхиленням від неї. Однак це не повинно бути перешкодою у захисті порушених прав.Висловлюється висновок, що внесення змін до абз. 1 ч. 2 ст. 16 ЦК України не спричинило абсолютного відходу від принципу numerus clausus способів захисту суб'єктивних цивільних прав на нерухоме майно, а лише надало суду можливість застосування для захисту прав спосіб захисту, який не суперечить закону, в умовах коли закон або договір взагалі не встановлюють ефективного способу захисту відповідних цивільних прав. При цьому через спеціально-дозвільний тип правового регулювання діяльності суду малоймовірним у відповідній ситуації є визначення судом способу захисту суб'єктивних цивільних прав на нерухоме майно, що взагалі не передбачений положеннями чинного цивільного законодавства України.

Cubic K2Ni0.5Hf1.5(PO4)3 crystallizes in the langbeinite structure type. The principal building units are two independent [(Ni,Hf)O6] octa­hedra, [PO4] tetra­hedra and [KO9] and [KO12] polyhedra., Polycrystalline potassium nickel(II) hafnium(IV) tris­(orthophosphate), a langbeinite-type phosphate, was synthesized by a solid-state method. The three-dimensional framework of the title compound is built up from two types of [MO6] octa­hedra [the M sites are occupied by Hf:Ni in ratios of 0.754 (8):0.246 (8) and 0.746 (8):0.254 (8), respectively] and [PO4] tetra­hedra are connected via O vertices. The K+ cations are located in two positions within large cavities of the framework, having coordination numbers of 9 and 12. The Hf, Ni and K sites lie on threefold rotation axes, while the P and O atoms are situated in general positions.

The photoelectrochemical properties of scheelite-related MIIxBi1−xV1−xMoxO4 (MII = Ca, Sr, x = 0.1 to 0.9) solid solutions deposited on conductive glass (coated with SnO2, F-doped) have been investigated as photoanodes in photoelectrochemical (PEC) water splitting. The variation of the final annealing temperature during the preparation of the conduction electrodes as well as the value of substitution x have been shown to affect the PEC performance. The micropowders of MIIxBi1−xV1−xMoxO4 (MII = Ca, Sr, x = 0.1 to 0.9) samples were first fabricated vi a solid-state method; they were characterised by SEM microscopy and powder and single crystal X-ray diffraction, and the band gap values were estimated using diffusive reflectance data. The value of substitution x = 0.1 in the cases of samples containing calcium and strontium affords the highest PEC performance reported for the whole range of substitution. These results demonstrate a promising approach for the beneficial utilization of BiVO4-substituted scheelite-related solid solutions in photo-electrochemical cells towards efficient and inexpensive photoanodes.

The evolution of high-performance and stable electrode materials for supercapacitors plays a vital role in the next generation of energy storage devices. In this work we present a simple method for preparing Bi(nanoparticles)/CNx(nanosheets) nanocomposites as electrode materials for supercapacitors, which were synthesized by thermally treating bismuth citrate and urea at 550-700 °C under an Ar atmosphere. According to physicochemical studies (XRD, SEM, TG-DTA, XPS, FTIR, and BET), a "smeared" bismuth formation or the formation of nanoparticles on the CNx surface of interwoven 2D-nanosheets at different calcination temperatures was observed. Electrochemical measurements show that the specific capacity of the composites can reach 1251 F g-1 (more than 90% of the theoretical value) at a current density of 500 mA g-1 in a 6 M KOH electrolyte, and most two-dimensional CNx-based nanostructures remain intact after multiple galvanostatic charge-discharge processes, which is promising for the development of highly efficient supercapacitors. A supercapacitor composed of Bi/CNx nanocomposites for the negative electrode and Ni-layered hydroxide for the positive electrode demonstrates a high energy density of 58 W h kg-1 with a power density of 800 W kg-1 accompanied by a good cycle life (the parameters decreased down to only 78% after 1000 charge-discharge cycles). Our current results indicate that the addition of urea not only determines the morphology of the composites, but also lays the foundation for the development of new types of nanocomposites for the power industry.

There is wide interest in developing efficient, robust and low-cost electrode materials for the electrolysis of water to produce clean hydrogen fuel. It is especially important to improve the performance and durability of electrocatalysts for the OER. Here we have shown that the transformation of nanoparticle (n-NNP) and crystalline (c-NNP) forms of mixed phosphate Na4Ni3(PO4)2P2O7 in highly alkaline solutions occurs along various routes and provokes the generation of 2D Ni(OH)2 nanosheets or stable core(phosphate)–shell(Ni(OH)2) particles, respectively. In both cases, in the carbon matrix (through chemical and electrochemical conversion of phosphate in situ during electrolysis in a 6 M KOH or NaOH solution) stable OER electrocatalysts with low overpotentials of 250–290 mV at a current density of 10 mA cm−2 were obtained. The best candidate for the OER process is core–shell particles, which maintain overpotentials of around 250 mV in 6 M KOH for more than 3 days. The activity enhancement can be attributed to the formation of abundant NiOOH nanoparticles on the shell surface due to improved lattice matching. This report discusses future prospects for the creation of core–shell particles to reduce the overpotential of durable electrocatalysts for the OER.

Manganites are multifunctional materials which are widely used in both technology and devices. In this article, new prospects of their use as nanoparticles for various types of applications are demonstrated. For that, the ferromagnetic nanopowder of La0.6Sr0.4MnO3 has been synthesized by the sol-gel method with a subsequent annealing at 700-900 °C. The crystal structure, phase composition and morphology of nanoparticles as well as magnetic, magnetothermal and electrocatalytic properties have been studied comprehensively. The critical sizes of superparamagnetic, single-domain, and multi-domain states have been determined. It has been established that an anomalously wide temperature range of magnetocaloric properties is associated with an additional contribution to the magnetocaloric effect from superparamagnetic nanoparticles. The maximum values of the specific loss power are observed in the relaxation hysteresis region near the magnetic phase transition temperature. The electrochemical stability and features of the decomposition of nanoparticles in 1 M KOH and Na2SO4 electrolytes have been determined. A decrease in the particle size contributes to an increase in electrocatalytic activity for overall water splitting. Magnetocaloric and electrocatalytic results of the work indicate the prospects for obtaining the possibility of changing the temperature regime of electrocatalysis using contactless heating or cooling.