Condensed Matter Physics, Materials Science, Renewable Energy, Sustainability and the Environment, Ecology
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Scopus Publications
Scopus Publications
FEATURES OF THE THERMAL BEHAVIOR AND PHASE FORMATION OF BiFeO3USING PRECURSORS ACTIVATED BY SOLAR MELTING M.S. Payzullakhanov, F.A. Giyasova, M.A. Yuldoshev, Ch.X. Toshpulatov, R.U. Ernazarov, et al. East European Journal of Physics, 2026 The effect of pretreatment of Bi2O3 and Fe2O3 oxides on the synthesis and structural characteristics of bismuth ferrite BiFeO3 was studied. It was found that BiFeO3 formation begins at 790÷850 °C, and decomposition occurs above ~920 °C. Preliminary melting of the oxides in a solar furnace shifts the thermal effects to higher temperatures and increases the thermodynamic stability of the phase. X-ray phase analysis revealed the formation of a perovskite-like structure with orthorhombic distortion, high crystallinity, and a crystallite size of 40±10 nm. Phase analysis confirmed an increase in the content of the main phase to 97 % and a decrease in the impurity phase Bi2Fe4O9. The obtained results confirm the efficiency of preliminary solar melting of oxides for the synthesis of high-quality ceramic materials based on BiFeO3.
Cascade Synthesis of Intermetallic PtZn Electrocatalysts for Practical Fuel Cells Shilong Xu, Siyuan Zheng, Yi Ding, Zhongyuan Li, Zihao Zhai, Yuan Kong, Yan Yan, Peng Rao, Ting Lei, Wenan Tie, Xiaoyan Tian, Di Wang, Mukhammad‐Sultankhan Payzullakhanov, Umedjon Khalilov, Nikolai N. Cherenda, Haiwei Liang, Mingkai Liu, Xinlong Tian Advanced Functional Materials, 2026 The performance of Pt‐based intermetallic electrocatalysts for the oxygen reduction reaction in practical fuel cells can be substantially enhanced via the phase engineering‐based regulation of strain effects. Herein, cascade synthesis exploiting a temperature‐dependent phase evolution process is used to prepare L10‐PtZn intermetallic compounds. ZnS produced in situ as an intermediate is shown to induce a sequential transformation of Pt to L12‐Pt3Zn and L10‐PtZn upon annealing. The resulting core/shell PtZn/Pt catalysts demonstrate a high mass activity of 1.18 A mgPt−1 at 0.9 V in a half‐cell test and a high current density of 0.98 A cm−2 at 0.7 V in a fuel‐cell test, experiencing a voltage drop of only 23 mV after 30 000 voltage cycles at 0.8 A cm−2. Density functional theory calculations and experiments indicate that the high activity of these catalysts is due to the strain effect caused by the lattice mismatch between the PtZn core and Pt (110) skin (and not Pt (111)). This study underscores the strategic use of phase‐engineering‐driven strain regulation in the design of high‐performance Pt‐based electrocatalysts for energy conversion applications.
Investigation of the Processes Involved in the Formation of Pyroxene Materials during Solar Melting in a Large Solar Furnace Muhammad S. Paizullakhanov, F. A. Giyasova, Khayot Bakhronov, Murodjon A. Yuldoshev, Alisher A. Mamadaliev, et al. Journal of Ovonic Research, 2026 The study investigates the influence of the parameters of concentrated light radiation (CLR) and the melt-cooling conditions on the structure formation, phase composition, and properties of pyroxene glass-ceramics. It is established that quenching the melt in water results in the formation of an amorphous glass, whereas reducing the cooling rate (~100 °C/s) leads to partial crystallization with the formation of diopside and augite phases. An increase in CLR flux density from 100 to 300 W/cm² promotes a higher degree of crystallinity, transitioning from a diopside– augite mixture to a monomineralic diopside–hedenbergite phase Ca(Fe,Mg)Si₂O₆. Increasing the flux density and the melt holding time is accompanied by an increase in apparent density (from ~2.70 to ~2.90 g/cm³) and a decrease in abrasion loss (from ~0.018 to ~0.008 g/cm³), indicating enhanced densification and wear resistance of the material. Optimal CLR conditions (≈300 W/cm², ~10³ °C/s) ensure the formation of a dense, homogeneous microstructure with low water absorption (0.02 %), high wear resistance (0.006 g/cm²), and a flexural strength of ≈145 MPa. The obtained results confirm the promise of pyroxene glass-ceramics for applications requiring thermally stable and wear-resistant materials.
Investigation of the functional capability of modified silicon-based photodiodes structure , Sh. B. Utamuradova, F. A. Giyasova, , M. S. Paizullakhanov, , S. Yu. Gerasimenko, , M. A. Yuldoshev, , S. R. Boydedayev, , M. R. Bekchanova, and Chalcogenide Letters, 2025 Based on the experimental data, the results of the study of photoelectric and gain characteristics of modified multi-barrier photodiode Au-nCdS-nSi-pCdTe-Au structures are presented, which are obtained by the method of vacuum evaporation in a quasi-closed volume by sputtering cadmium sulfide and cadmium telluride layers on a silicon substrate with a specific resistance of 607.47 Ohm⋅cm. It is shown that the structures in the passing direction of the current at low illumination levels operate as injection photodiodes, and also the optical spectral range (0.3÷0.95 μm) covers from the nSi-pCdTe-Au side and (1.0÷1.4 μm) from the Au-nCdS-nSi side with a photosensitivity of 0.57 A/W at a wavelength of 1310 nm. In addition, the possibility of their application in optical power attenuation meters is considered.
Sodium Ferrate Synthesized in a Solar Furnace: a Cathode Material for a Sodium-Ion Battery M. S. Paizullakhanov, O. R. Parpiev, E. Z. Nodirmatov, M. Kh. Bazarova, Sh. Sh. Shosaitov Technical Physics Letters, 2025 Abstract It has been shown that a material based on sodium ferrate NaFeO2 can be obtained by synthesis from a melt in a solar furnace. The crystal structure is tetragonal with the lattice parameters of a = 5.638 Å, b = 5.672 Å, and c = 7.279 Å. The average particle size of the material is 1.2 μm. It has been found that the NaFeO2 material sample provides the oxidation–reduction activity of Na+/Na and the oxidation–reduction activity of Fe2+/Fe3+. Therefore, NaFeO2 can be a potential material for the cathode of a sodium-ion battery with a specific capacity of 110 mAh/g. It has been found that sodium ferrate NaFeO2 exhibits sufficiently good resistance to water. That is, sodium ferrate does not decompose in water at 80–100°C.
STUDY ON CHANGES IN PORE SIZE ON SINGLE POWDER AND REDUCTION SWELLING INDEX DURING THE REDUCTION OF IRON MILL SCALE WITH HYDROGEN AND FORMING GAS Mukhammad Sultonkhon Paizullakhonov, Sanjar Abduraimov, Oleksandr Kovtun, O. Volkova, Samar Abduraimov High Temperature Material Processes, 2025 In this research study, we examined the impact of hydrogen content, temperature, and reaction time in reducing the mill scale and porosity formation on a single powder. Reduction reactions were carried out at temperatures ranging from 700&deg;C to 1000&deg;C under hydrogen and forming gas (80 vol&#37; N<sub>2</sub>/20 vol&#37; H<sub>2</sub>). The utilization of hydrogen as a reducing agent has been identified as leading embrittlement and the creation of porous configurations. In this study, we examined the porosity structures on the single powder formed during the reduction of iron oxides using two different reducing gases. The results indicated an increase in the degree of reduction and porosity size on the single powder with increasing temperature for both hydrogen and hydrogen/nitrogen mixtures.
Optical-Energy Characteristics and Heating Temperatures in Small Single-Mirror Solar Furnaces Sh. I. Klychev, S. A. Bakhramov, O. R. Parpiev, M. S. Paizullakhanov, L. S. Suvonova, D. E. Kadyrgulov, E. K. Matjanov, F. A. Giyasova Applied Solar Energy English Translation of Geliotekhnika, 2024 Abstract The possibilities of using single-mirror small solar furnaces (SSFs) with concentrators made of spotlight mirrors in high-temperature materials science are investigated. Calculated estimates of the optical-energy characteristics (OECs) of spotlight mirrors as SSF elements (average concentrations and flux distribution in the focal plane depending on the mirror inaccuracies) are carried out. Experimental studies of SSFs with a spotlight mirror with a diameter of 2 m and an opening angle of 60° showed that they can provide average flux densities of concentrated solar radiation up to 600–700 W/cm2 on a working spot with a diameter of up to 10–15 mm and provide heating temperatures above 3000 K. The results of the study show the possibilities of using SSFs with a parabolic spotlight mirror with a diameter of 2 m in high-temperature materials science, both at the research stage and at the stages of developing the technology for obtaining functional materials in the Large Solar Furnace.
Hydrogen Storage on Porous Absorbers with a Zeolite Composition M. S. Paizullakhanov, O. R. Parpiev, Zh. Z. Shermatov, E. Z. Nodirmatov, O. T. Rajamatov Applied Solar Energy English Translation of Geliotekhnika, 2024 Abstract The processes of hydrogen absorption in porous ceramic materials have been studied. The results of the synthesis of porous materials for use in hydrogen absorbers are presented. The dependences of the degree of hydrogen absorption on the composition of the absorber, as well as on the temperature of hydrogen sorption, are obtained. It is shown that aluminosilicate materials synthesized from raw materials fused in a solar furnace with a specific surface area of 2500 cm2/g can be used as hydrogen absorbers for the physical binding of hydrogen in pores by Van der Waltz forces at high (30–50 atm) pressures. It was revealed that the aspect number, i.e., the ability of the material to absorb hydrogen at 200°C, varies from composition to composition. The maximum value of the aspect number (4.3 wt %) corresponds to a material with a diatomite content of 70 wt % and burnout additives of 20% by weight. It is shown that a porous material based on AlSiNaO sodium aluminosilicate with lattice parameter a = 4.056 А is a good hydrogen absorber. With an increase in the temperature of the sorption process from 100 to 190°C, the value of the aspect number increases from 3 wt % up to 13 wt %.
Studying the Possibility of Applying Barium-Strontium Cobaltite in Hydrogen Energy M. S. Paizullakhanov, N. Kh. Karshieva, F. N. Ernazarov, S. M. Abduraimov, S. S. Sabirov Thermal Engineering, 2024 Anion-deficient structures based on $${\text{S}}{{{\text{r}}}_{{0.5}}}{\text{B}}{{{\text{a}}}_{{0.5}}}{\text{C}}{{{\text{o}}}_{{1 - x}}}{\text{F}}{{{\text{e}}}_{x}}{{{\text{O}}}_{{3 - \delta }}}$$ synthesized from a melt in a stream of concentrated solar radiation with a density of 100–200 W/cm2 created in a large solar furnace (LSF) were studied. Briquettes in the form of tablets made on the basis of a stoichiometric mixture of carbonates and metal oxides ( $${\text{SrC}}{{{\text{O}}}_{3}}$$ + $${\text{BaC}}{{{\text{O}}}_{3}}$$ + $${\text{C}}{{{\text{o}}}_{2}}{{{\text{O}}}_{3}}$$ + $${\text{F}}{{{\text{e}}}_{2}}{{{\text{O}}}_{3}}$$ ) were melted in a water-cooled melting unit in the LSF focal zone. Drops of the melt flowed into the water in a container located 40 cm below the melting unit. Such conditions contributed to the cooling of the melt at a rate of 103 K/s. The castings were ground to a grinding fineness of 63 microns, dried at 673 K, and samples were molded from the resulting powder using semidry pressing (at a pressure of 100 MPa) in the form of tablets with a diameter of 20 mm and a height of 10 mm. The tablets were sintered in air at a temperature of 1050–1250°C. The structure, water absorption, and electrical properties of the finished samples were studied. The crystal lattice of the material had a perovskite structure with a unit cell parameter A = 4.04 × $${{10}^{{ - 10}}}$$ m of space group Рm3m. The area of homogeneity of compositions $${\text{S}}{{{\text{r}}}_{{0.5}}}{\text{B}}{{{\text{a}}}_{{0.5}}}{\text{C}}{{{\text{o}}}_{{1 - x}}}{\text{F}}{{{\text{e}}}_{x}}{{{\text{O}}}_{{3 - \delta }}}$$ corresponded to the interval x = [0; 0.7], where x is the amount of element introduced instead of the main one. The most optimal composition in terms of stability of structure and properties was $${\text{S}}{{{\text{r}}}_{{0.5}}}{\text{B}}{{{\text{a}}}_{{0.5}}}{\text{C}}{{{\text{o}}}_{{0.8}}}{\text{F}}{{{\text{e}}}_{{0.2}}}{{{\text{O}}}_{{2.78}}}$$ . The average crystallite size of the obtained materials is 30–40 μm. The grains are predominantly in the form of spherulites and curved cylinders. Samples of the material showed high resistance to water vapor. The values of structural parameters indicate that the material made from $${\text{S}}{{{\text{r}}}_{{0.5}}}{\text{B}}{{{\text{a}}}_{{0.5}}}{\text{C}}{{{\text{o}}}_{{0.8}}}{\text{F}}{{{\text{e}}}_{{0.2}}}{{{\text{O}}}_{{2.78}}}$$ can be used as a catalyst in the generation of hydrogen and synthesis gas through reforming and oxidation of methane.
Biogas Production based on Thermophilic Methanogenic Fermentation of Chicken Manure A. A. Makhsumkhanov, O. M. Pulatova, B. Kh. Alimova, Sh. T. Sadullaev, Sh. A. Tashbaev, A. R. Sarynsakhodzhaev, M. K. Karimov, M. K. Kurbanov, D. Sh. Saidov, U. B. Sharopov, K. Yu. Rashidov, A. Yu. Usmanov, Zh. Z. Shermatov, M. S. Payzullakhanov Applied Solar Energy English Translation of Geliotekhnika, 2023
SOLAR TECHNOLOGY FOR METALLURGICAL WASTE PROCESSING Mukhammad S. Paizullakhanov, Odilhuja R. Parpiev, Rasuljan Yu. Akbarov, Abdurashid A. Holmatov, Nilufar H. Karshieva, Nikolai N. Cherenda High Temperature Material Processes, 2023
Pyroxene Material Melted in a Solar Furnace M. S. Paizullakhanov, O. R. Parpiev, E. Z. Nodirmatov, Zh. Z. Shermatov, O. T. Razhamatov, G. Sh. Karimova, M. M. Sulaimanov, F. N. Ernazarov Applied Solar Energy English Translation of Geliotekhnika, 2021
Synthesis of MATERIALS by CONCENTRATED SOLAR RADIATION M. S. Paizullakhanov, Zh. Z. Shermatov, E. Z. Nodirmatov, O. T. Rajamatov, F. N. Ernazarov, M. T. Sulaimanov, Sh. Nurmatov, Nikolai N. Cherenda High Temperature Material Processes, 2021
Measurement of the structural and electrophysical parameters of the superconducting texturized ceramic YBa2Cu3O7-δ after ultrasonic treatment Russian Ultrasonics, 1993
