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Item Open Access BIOMASS GRAPHENE DERIVED FROM DATE SEEDS AS AN ANODE MATERIAL FOR LITHIUM-ION BATTERY(National Laboratory Astana, 2022-08) Tassybay, Kazna; Issatayev, Nurbolat; Kalimuldina, Gulnur; Nurpeissova, Arailym; Bakenov, ZhumabayLithium-ion batteries (LIBs) are in great demand as energy storage systems applied in wide range of electronic devices. However, currently used commercial anodes have a limited capacity of 372 mAh g -1. Therefore, development of novel carbon materials for high performance electrodes is of high interest. Recently, biomasses have attracted much attention as electrode materials for LIBs due to their low cost and environmental sustainability. In this research, a nitrogen-doped porous biomass graphene material was prepared from date seeds as an organic matter through carbonization and chemical activation.Item Open Access DETERMINATION OF OPTIMAL SYNTHESIS CONDITIONS OF THE CU@PET COMPOSITES USING TAGUCHI ROBUST EXPERIMENT DESIGN(National Laboratory Astana, 2022-08) Mashentseva, Anastassiya; Zdorovets, MaximIn this task the Taguchi robust design was applied to optimize experimental parameters as well as to determine the optimal conditions for the electroless copper plating. Taguchi robust planning is widely used in the production and study of various technological processes and scientific research, including synthesis of nanomaterials and the study of their properties...Item Open Access MICROWAVE-ASSISTED SYNTHESIS OF LISICON STRUCTURED LI3V2(PO4)3/ GRAPHENE COMPOSITE(National Laboratory Astana, 2022-08) Mukushev, Ilyas; Nurpeissova, Arailym; Kalimuldina, Gulnur; Bakenov, ZhumabayOne of the main challenges in cathodes at low temperatures (LT) is associated with low electronic and ionic conductivity. Graphene can be used to increase electronic conductivity, but most of the experimental methods for graphene composites require long-term high-temperature treatment and an inert atmosphere, which causes high energy consumption and cost increase. In comparison, microwave heating can simplify the reduction step of graphene oxide and provide a convenient, economical, and effective method of preparing graphene composites. LISICON structured Li3V2(PO4)3 (r-LVP) was reported to have enhanced LT performance due to high alkali- ion mobility and rhombohedral structure with the open framework.Item Open Access BIOMASS-DERIVED GRAPHITE AS AN ANODE MATERIAL FOR HIGH-PERFORMANCE LI-ION BATTERIES AT LOW TEMPERATURE(National Laboratory Astana, 2022-08) Issatayev, Nurbolat; Tassybay, Kazna; Kalimuldina, Gulnur; Nurpeissova, Arailym; Bakenov, ZhumabayIn this study, we purpose alternative biomass-derived porous graphitic carbon from date seeds as anode material for a low-temperature lithium-ion battery. The as-obtained graphite was characterized by X-ray diffractometry, scanning electron microscope, Raman scattering and X-ray photoelectron spectroscopy. The honeycombed structure of graphite shortens the diffusion path and provides excellent anode properties, showing high specific capacity at low temperatures.Item Open Access PHOTODETECTORS MADE OF CARBON NANOWALLS TRANSFERRED ON SI AND CDTE(National Laboratory Astana, 2022-08) Zhumadilov, Rakhymzhan; Yerlanuly, Yerassyl; Parkhomenko, Hryhorii P.; Jumabekov, Askhat N.Carbon nanowalls (CNWs) are few-layer graphene nanosheets standing vertically on a substrate. CNWs can be synthesized on various metallic, semiconductor and insulator substrates using various techniques. CNWs demostrate unique structure and special optoelectronic properties, which makes them a promising material for various optoelectronic applications.Item Open Access SOL-GEL SYNTHESIS OF LIFEPO4 FOR LIB BASED ON LITHIUM CARBONATE FROM KAZAKHSTANI SPODUMENE FEEDSTOCKS(National Laboratory Astana, 2022-08) Zhanabayeva, Assem; Nalibayeva, Arailym; Zhumabayeva, Dinara; Abdykhalykov, ErlanLiFePO4 (LFP) cathode material with an olivine structure, in comparison with other cathode materials, has a number of positive properties, such as: high theoretical capacity and stability, low cost and environmental friendliness. The sol-gel method is one of the effective single-step methods for the production of LFP to control the structure of the electrode materials and provide a nanostructured homogeneous composition of the product particles. LFP was synthesized by sol-gel method from high-purity lithium carbonate obtained from spodumene raw materials of Kazakhstani deposits.Item Open Access BIOMASS-BASED BIOCHAR OBTAINED BY LOW-TEMPERATURE PYROLYSIS IN THE PRESENCE OF METAL OXIDES: PREPARATION, CHARACTERIZATION AND FUTURE APPLICATIONS(National Laboratory Astana, 2022-08) Aitbayeva, Aigerim; Uali, Aitolkyn; Shlyapov, Rustam; Vishnyakov, Alexey; Amerkhanova, ShamshiyaBiochar, which is material obtained from biomass by thermochemical decomposition, is an environmentally friendly replacement for carbon materials. Its applications range from heat and energy production, agriculture and livestock farming to analytical chemistry and analysis. This carbon-enriched material can be obtained by using microwave-assisted pyrolysis, hydrothermal carbonization, pyrolysis, and gasification, thus changing the product's structure and propertiesItem Open Access ESTABLISHMENT OF REGULARITIES OF THE INFLUENCE OF FACTORS THAT DETERMINE THE ELECTROCHEMICAL STABILITY WINDOW OF AQUEOUS ELECTROLYTES FOR SODIUM-ION BATTERIES(National Laboratory Astana, 2022-08) Akatay, T.A.; Kurbatov, A.P.; Kohmetova, S.T.The use of water as a battery electrolyte provides better ion migration. Also, an aqueous electrolyte is more environmentally friendly and safe, the low price of such electrolytes is also important, in addition, water is an excellent solvent for many salts...Item Open Access MAXIMIZING SPECIFIC CAPACITY OF NUTTY HARD CARBON: IMPACT OF TREATMENT CONDITIONS ON STRUCTURAL AND ELECTROCHEMICAL PROPERTIES(National Laboratory Astana, 2022-08) Bazybek, Nardana; Maratov, Maksat; Konarov, AishuakHard carbon (HC) has attracrted tremendous attention in sodium ion batteries (SIBs) as promising negative electrode material due to its low cost, environmental friendliness and stable cyling performance. However, due to the limited capacity and low initial columbic efficiency (ICE), the actual full cell application of HC faces significant obstacles. Therefore, preparation process was optimized to investigate the impact of the pre-treatment conditions and degree of graphitization on electrochemical performance and to resolve abovementioned problems.Item Open Access STRUCTURE AND ELECTRONIC PROPERTIES OF LAYERED GE-SB-TE BASED ALLOYS(National Laboratory Astana, 2022-08) Tolepov, Zhandos; Prikhod’ko, Oleg; Zhakupov, Alibek; Tursyn, Yernar; Rakhi, AssyltasCurrently, with the increasing demands for modern storage media, such as flash memory (flash-memory) and hard disks based on magnetic recording, there is a failure of these types of storage media. This is mainly due to the insufficient number of write and erase cycles, the speed of writing and reading information, low radiation resistance, etc. [1-3]. In this regard, the expected receiver of a new generation of information carriers are non-volatile phase memory elements (PCM - Phase Change Memory) based on chalcogenide glassy semiconductors (CGS)Item Open Access LIMITATIONS AND CAPABILITIES OF MICRO-RAMAN SPECTROSCOPY. ELECTRODE MATERIALS FOR LITHIUM BATTERY(National Laboratory Astana, 2022-08) Ryabin, Alexander; Nikiforov, Alexei; Pelegov, DmitryRaman spectroscopy is an inexpensive and convenient tool for prompt structural characterization. Most research groups have access to confocal Raman microscopes with claimed submicron spatial and subsecond temporal resolutions. Raman spectroscopy is widely used in material science, solid- state chemistry, and electrochemistry. But this unique tool is often considered to be auxiliary to other methods and is commonly used as a “black box” without proper understanding of its limitations and capabilitiesItem Open Access EFFECT OF ACID ETCHING OF STAINLESS-STEEL FOILS IN RECHARGEABLE LITHIUM-ION BATTERIES(National Laboratory Astana, 2022-08) Maratova, Kamila; Konarov, Aishuak; Umirov, Nurzhan; Bakenov, ZhumabayResearch into rechargeable aqueous batteries is driven by the need for low-cost, high-safety batteries for large-scale energy storage applications. The effect of current collectors on battery performance is frequently disregarded, despite the fact that the majority of research efforts concentrate on creating electrolyte formulations and electrode materials.Item Open Access BINDING, REACTION, AND ACTIVATION ENERGIES OF OH- IONS INTERACTING AND REACTING TO SOME HEAD GROUPS OF ANION EXCHANGE MEMBRANE EXPLORED VIA THE DFT METHOD(National Laboratory Astana, 2022-08) Karibayev, Mirat; Myrzakhmetov, Bauyrzhan; Kalybekkyzy, Sandugash; Mentbayeva, Almagul; Wang, YanweiThe main drawback of Anion Exchange Membranes is related to the chemical instability of cationic head groups and the transportation of hydroxide ions at alkaline conditions and elevated temperatures. At this stage, our research was devoted to understanding the stability and transportation mechanism of hydroxide ions in detail and aiming to reach and keep the performance of AEM for a long time. In this regard, the quantum chemical properties for binding of various hydroxide ion-quaternary ammonium (QA) head group systems were investigated by the DFT method in implicit water to get binding energy. Then, the nucleophilic subsition degradation reaction of various hydroxide ion-QA head group systems were studied by the DFT method at the different hydration levels. Finally, the results of the DFT methods were in line with experimental results on chemical stability and ion exchange capacity.Item Open Access ANALYSIS OF RIM-DRIVEN TURBINES: A LITERATURE REVIEW(National Laboratory Astana, 2022-08) Jyeniskhan, Nursultan; Zholdybayev, Akezhan; Arystanbekov, Chingiz; Gouda, SherifOne of the common and convenient methods for generating electricity from the marine environment is extracting energy from the water containing kinetic energy. Due to environmental concerns, rim-driven turbines are proposed, with several advantages such as efficiency due to compact design and reduced failure rates. This review paper aims to evaluate the various aspects of turbines to denote the necessity of applying Rim-driven turbinesItem Open Access NOVEL ORGANIC MATERIALS FOR NON-AQUEOUS REDOX FLOW BATTERIES: IMPLEMENTATION OF TRIARYLAMINE AND PHENAZINE CORE STRUCTURES(National Laboratory Astana, 2022-08) Romadina, Elena; Akkuratov, Alexander V.; Stevenson, Keith J.The rapid growth of the role of renewable energy sources dictates new requirements for the electrochemical energy storage devices. Among them, redox flow batteries (RFBs) are regarded as a promising technology, since their advantages of excellent scalability, low cost, easy fabrication and operation, long lifetime, and safety. Today inorganic RFBs are penetrating the market, however, low specific capacity in conjunction with with low electrochemical stability window of aqueous electrolytes (≈1.5 V) and safety issues, hinders their wide-scale commercialization.Item Open Access PT-FREE AND EFFICIENT COUNTER ELECTRODE WITH NANOSTRUCTURED MNCO2S4 FOR DYE-SENSITIZED SOLAR CELLS(National Laboratory Astana, 2022-08) Suleimenova, Diana; Ibrayeva, Ayagoz; Baptayev, Bakhytzhan; Tashenov, Yerbolat; Balanay, Mannix P.In the past few years, the development of alternative and renewable energy sources has been one of the urgent and most important tasks due to the growing demand of the population for energy. Dye-sensitized solar cells (DSSC) firstly introduced by Grätzel and O'Regan are third generation photovoltaic devices that have distinctive advantages over silicon solar cells, such as low cost of materials used, ease of fabrication and eco-friendliness.Item Open Access A STUDY OF CU-DOPING EFFECTS IN NA2MN3O7 LAYERED CATHODE MATERIAL FOR SODIUM-ION BATTERY(National Laboratory Astana, 2022-08) Rakhymbay, Lunara; Konarov, Aishuak; Bakenov, ZhumabayIn recent years, sodium-ion batteries (SIBs) attracted great attention owing to their rich Earth-abundant resources, environmental friendliness, low cost, and high energy efficiency. To be compared to lithium-ion batteries the developing advanced cathodes play a key role in enhancing the performance of SIBs. Layered transition metal oxides NaxMO2 (M = Co, Mn, Fe, Ni, etc.) are one of the promising cathodes for SIBs due to the variable composition, abundant active center, and good electrochemical performance.Item Open Access P-DOPED COFFEE GROUND-DERIVED HARD CARBON FOR BOOSTING SODIUM-ION BATTERIES(National Laboratory Astana, 2022-08) Kalibek, Madina; Konarov, Aishuak; Bakenov, ZhumabayThe paper proposed the facile and successful preparation of P-doped coffee ground-derived hard carbon using H3PO4 as a dopant material for sodium-ion batteries. The manipulation with 1-3 M of H3PO4, contributed to finding the optimal concentration for the maximum incorporation of phosphorus ions into the carbon framework. The use of 2 M of H3PO4 dopant material for hard carbon as anode for sodium-ion battery delivers promising electrochemical performanceItem Open Access STRUCTURAL AND MECHANICAL PROPERTIES OF HEAT RESISTANT TITANIUM ALLOWS OF THE TI-24.5AL-24.5NB (AT.%) SYSTEM(National Laboratory Astana, 2022-08) Mukhamedova, Nuriya; Miniyazov, Arman; Kozhakhmetov, YernatHeat resistant titanium alloys with various types of microstructure and homogeneous distribution of components were obtained using high-energy processing of powder mixtures in a planitary mill, followed by spark plasma sintering (SPS). Isothermal sections of the Ti-24,5Al- 24,5Nb (at.%) system at SPS (1000, 1200 and 1300°C, 1550) were studied using X-ray diffraction, scanning electron microscopy and energy-dispersive spectral analysis. Three-point bending mechanical tests were carried out at room temperature on Instron 5966 universal testing machine...Item Open Access CHARGE-TRANSPORT MATERIALS IMPACT ON THE PEROVSKITE SOLAR CELLS STABILITY(National Laboratory Astana, 2022-08) Novikov, Artyom; Tepliakova, Marina; Yamilova, Olga; Frolova, Lyubov; Shilov, Gennady; Dremova, Nadezhda; Zhidkov, Ivan; Kurmaev, Ernst; Troshin, Pavel; Stevenson, KeithPerovskite solar cells (PSCs) represent one of the most promising photovoltaic technologies now reaching power conversion efficiency (PCE) values more than 25%. However, their commercialization is still hindered by the poor stability of complex lead halides comprising their active layer. It was shown repeatedly in previous works that charge-transport materials (CTMs) employed in PSCs can affect their operational stability significantly by reacting with the perovskite materials or, in contrast, protecting the perovskite. Yet, to date, there have been no systematic investigation of this issue