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EN
This investigation concerns the synthesis as well as structural and morphological characterizations of pure and Ce-doped ZnO nanorods. The samples were synthesized by simple low-temperature hydrothermal process using respectively NaOH and KOH as caustic bases. The as-synthesized nanorods were characterized in terms of their morphological, structural, compositional and vibrational properties. The sizes of the rods were found to be 1.5 μm to 2 μm in length and 250 nm to 300 nm in diameter. The presence of Ce ions in ZnO (NaOH) favored the agglomeration of the rods to form flower-like nanostructures. EDAX measurements showed Zn rich materials with high oxygen vacancy concentration. XRD results indicated that the synthesized ZnO nanorods possess a pure wurtzite structure with good crystallinity. It has also been found that Ce doping deteriorates the crystalline quality of ZnO (NaOH) and improves that of ZnO (KOH). The insignificant intensities observed in FT-IR signals confirm that the synthesized nanorods are of high purity. The Raman spectroscopy studies showed that Ce ions shift the vibrational modes towards lower frequencies. The peaks related to E2 (high) mode in ZnO (KOH) are relatively intense compared to those of ZnO (NaOH). The peaks are found to be shifted and asymmetrically broadened due to anharmonic effects originating from quantum-phonon-effect confinement.
2
Content available remote Kruszywo xonotlitowe - część II: Charakterystyka produktów syntezy
PL
Celem pracy było wytworzenie krystalicznego xonotlitu z tanich i powszechnie dostępnych surowców, takich jak wapno gaszone i mączka kwarcytowa oraz charakterystyka produktów syntezy hydrotermalnej. Krystaliczny xonotlit, bez udziału nieporządnych faz węglanowych, otrzymano dopiero po zastosowaniu 10-godzinnej syntezy przy ciśnieniu 3 MPa w atmosferze ochronnej argonu. Produkt autoklawizacji jest stabilny termicznie do temperatury 700°C, po przekroczeniu której następuje jego stopniowa dehydroksylacja, a następnie przemiana w wollastonit. Wytworzony xonotlit ma niewielką rozszerzalność cieplną, świadczącą o jego dobrej stabilności wymiarowej do temperatury krystalizacji niskotemperaturowej odmiany polimorficznej wollastonitu wynoszącej ok. 800°C, co sprawia, że może on stanowić dobry półprodukt do produkcji lekkich materiałów izolacyjnych.
EN
The aim of the work was to obtain crystalline xonotlite from cheap and commonly available raw materials, such as hydrated burnt lime and quartz flour, and properties of synthesis products. Crystalline xonotlite, without any unwanted carbonate phases, was only obtained after applying a protective atmosphere during ongoing synthesis for 10 and 24 hours, at a pressure of 3 MPa. The product of autoclaving displays thermal stability up to 700°C and after exceeding this temperature, it is gradually dehydroxylated, and next, transformed into the low-temperature polymorphous form of wollastonite. The obtained xonotlite is characterized by slight thermal expansion, indicating its good dimensional stability up to a temperature of crystallization of wollastonite, reaching about 800°C, which makes it a good half-product for the production of light insulating materials.
EN
The objectives of our study were to prepare of ZSM-5 and USY-based catalysts by hydrothermal method, containing metallic active phase, deposited by both conventional ionic-exchange or ultrasonic irradiation. Prepared materials were characterized by various physicochemical methods, such as XRD, BET, SEM, UV-VIS and the sorption of ammonia monitored by FT- -IR spectroscopy. The XRD data confirmed pure MFI or USY type structure zeolite. BET and ammonia sorption results have shown that the presented method leads to preparation of highly porous and acidic systems. Metallic active phase was found as cations and oxides with hexagonal and octahedral coordination.
4
Content available remote Kruszywo xonotlitowe, część I: Synteza hydrotermalna
PL
W związku z dużym perspektywicznym znaczeniem xonotlitu dla gospodarki narodowej, podjęto badania jego syntezy hydrotermalnej. W doświadczeniach stosowano powszechnie dostępne surowce, z mianowicie piasek kwarcowy, zmielony do wielkości cząstek mniejszych od 0,2 μm, oraz wapno hydratyzowane. W celu całkowitego usunięcia węglanów wapno prażono w temperaturze 1000°C, a syntezę xonotlitu prowadzono w atmosferze argonu. Przeprowadzone doświadczenia wykazały, że synteza hydrotermalna pod ciśnieniem 3 MPa i w czasie, wynoszącym 10 godzin pozwala na otrzymanie krystalicznego xonotlitu, o pokroju pręcikowatym. Natomiast wydłużenie czasu syntezy do 24 godzin zmienia znacznie morfologię xonotlitu i wielkość kryształów.
EN
In connection with the perspective importance of xonotlite for the national economy, the study of its thermal synthesis, was undertaken. In the experiments the commonly accessible raw materials were used, namely the quartz sand, ground to the particles sizes under 0.2 μm and slaked lime. In order to totally eliminate the carbonates from lime, it was preliminary burned at 1000°C and the xonotlitu synthesis was conducted in the argon atmosphere. The experiments have shown that the hydrothermal synthesis, under the pressure of 3 MPa and during the period of 10 hours, is sufficient for the crystalline xonotlite formation, with the fibrous morphology. However, the time elongation to 24 hours, was changing very much the crystals sizes and morphology.
PL
W artykule zbadano możliwość wykorzystania popiołów lotnych klasy C (otrzymywanych w wyniku spalania węgla brunatnego w kotle pyłowym) i F (otrzymywanych w wyniku spalania węgla kamiennego metodą konwencjonalną) jako substratów do syntezy materiału zeolitowego z grupy filipsytu. W tym celu przeprowadzono szereg syntez hydrotermalnych z wykorzystaniem reagentów takich jak wodorotlenek sodu (NaOH) oraz bromek tetrapropyloamoniowy (TPABr). W wyniku reakcji otrzymano docelowy materiał zeolitowy, zarówno z popiołu klasy C, jak i F. Otrzymane produkty syntezy, jak też popiołowe substraty reakcji, poddano charakterystyce chemicznej i mineralogicznej. Badania wykazały, że popiół lotny powstały z węgla brunatnego i kamiennego może być substratem w reakcjach syntez zeolitu, jakim jest filipsyt. Analiza porównawcza dyfraktogramów rentgenowskich produktów z obu typów popiołów wykazała, że lepszym substratem jest popiół klasy C otrzymywany w wyniku spalania węgla brunatnego w kotle pyłowym (w reakcji syntezy otrzymano lepiej wykształcone formy zeolitowe). W pracy dokonano także analizy literaturowej potencjalnych kierunków zastosowania filipsytu w inżynierii i ochronie środowiska. Na podstawie zweryfikowanych danych stwierdzono, iż dalszym kierunkiem badań będzie analiza możliwości wykorzystania otrzymanych materiałów jako potencjalnych sorbentów amoniaku.
EN
The study examined the possibility of using class C fly ash (obtained as a result of brown coal combustion in a pulverized-fuel boiler) and class F (obtained as a result of conventional coal combustion) as substrates for the synthesis of zeolitic material from the phillipsite group. For this purpose, a series of hydrothermal syntheses were carried out using reagents such as sodium hydroxide (NaOH) and tetrapropylammonium bromide (TPABr). As a result of the reaction, the target zeolite material was obtained from both class C and F fly ash. The obtained synthesis products as well as the ash reaction substrates were subjected to chemical and mineralogical characterization. The studies have shown that fly ash formed from brown coal and hard coal may be a substrate in zeolite synthesis reactions to obtain phillipsite. A comparative analysis of X-ray diffractograms of products from both types of ash showed that class C ash obtained as a result of brown coal combustion in a pulverized-fuel boiler is a better substrate (in the synthesis reaction better-formed zeolites were obtained). The article also includes a literature analysis on the potential applications of phillipsite in engineering and environmental protection. Based on the verified data, it was found that the further direction of the research will be the analysis of the possibilities of using the obtained materials as potential ammonia sorbents.
EN
Self-assembled Zn/ZnO microspheres have been accomplished on selected sites of boron doped P-type silicon substrates using hydrothermal approach. The high density Zn/ZnO microspheres were grown on the Si substrates by chemical treatment in mixed solution of zinc sulfate ZnSO4·7H2O and ammonium hydroxide NH4 (OH) after uniform heating at 95 degrees C for 15 min. The Zn/ZnO microspheres had dimensions in the range of 1 pm to 20 pm and were created only on selected sites of silicon substrate. The crystal structure, chemical composition and morphology of as-prepared samples were studied by using scanning electron microscope SEM, X-ray diffraction XRD, energy dispersive X-ray spectroscopy EDS, Fourier transform infrared spectroscopy FT-IR and UV-Vis diffuse reflectance absorption spectra DRS. The energy band gap Eg of about 3.28 eV was obtained using Tauc plot. In summary, this study suggests that interfacial chemistry is responsible for the crystal growth on indented sites of silicon substrate and the hydrothermal based growth mechanism is proposed as a useful methodology for the formation of highly crystalline three dimensional (3-D) Zn/ZnO microspheres.
EN
Cotton-like CoS cluster has been successfully synthesized via a simple one-step hydrothermal route assisted by diethylenetriamine (DETA) as a ligand and structure-directing agent. The structure and morphology of the product were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and N2 adsorption-desorption isotherm. The CoS sample which has a hexagonal phase without any impurities possesses a microscopic morphology made by cotton-like clusters. The as-fabricated CoS as a supercapacitor electrode presents desirable supercapacitive performance with a high specific capacitance (664 F·g-1 at 0.5 A·g-1), remarkable rate capability and excellent cycling stability (85.7 % specific capacitance retention after 1000 cycles), making it applicable as an electrode for high-performance supercapacitors.
8
Content available Preparation of Synthetic Zeolites from Fly Ash
EN
The paper deals with the possibility of utilizing fly ash generated during coal combustion as an input material for the hydrothermal synthesis process in order to prepare a mineral phase. In the hydrothermal synthesis process, we worked with 2M and 3M sodium hydroxide, different process times from 6h to 24h and temperature range 90–110°C. Prior to the experiment, we analysed the input fly ash using XRF, XRD, and SEM. Based on the results, we selected appropriate fly ash and carried out hydrothermal synthesis of zeolites. The resulting mineral phases were analysed by XRD and SEM.
PL
Artykuł jest poświęcony możliwości wykorzystania popiołu lotnego ze spalania węgla jako materiału wejściowego do procesu syntezy hydrotermalnej w celu przygotowania fazy mineralnej zeolitu. W procesie syntezy hydrotermalnej wykorzystano 2M i 3M wodorotlenek sodu, proces prowadzono w czasie od 6h do 24h i w zakresie temperatur 90–110°C. Przed eksperymentem przepro¬wadzono analizy XRF, XRD i SEM popiołu. Na podstawie uzyskanych wyników wybrano odpowiedni popiół lotny i przeprowadzono hydrotermalną syntezę zeolitów. Powstałe fazy mineralne analizowano za pomocą XRD i SEM.
9
EN
Purpose: At thermal power plants the fly ash (FA) is stored either through dry or wet disposal systems. These storage practices result in different features for fly ashes, such as their interaction with alkalis and hence the potential of zeolite synthesis will be different. With the aim to demonstrate this, it was conducted some investigations to study the physical, chemical, morphological and mineralogical characteristics of the fly ash residues, then were used to synthesis zeolites by a double stage fusion-hydrothermal method. Design/methodology/approach: The raw and converted fly ash samples were characterized with respect to their composition, crystallinity and morphology, by SEM and XRD analysis. The effects of environment conditions and process parameters on the zeolitization process were studied and analysed. Findings: The analysis of these residues showed that dry ash attains a high cation exchange capacity (CEC) and SiO2 /Al2O3 ratios, which is in agreement to the formation of fly ash zeolites as compared to its counterpart. The experimental results indicate that the fusion temperature does not influence on the synthesis mechanism in range of 500-800 (°C) having only an effect of acceleration. The increasing of alkaline activator/fly ash ratio enhances the zeolitization degree. Research limitations/implications: The scientific basis for the issues on the zeolitization characteristics of fly ash and its use to manufacture porous materials calls yet for further elucidation and development. Practical implications: This study helps to establish the superiority of dry ash over wet ash for synthesizing porous materials and their enhanced quantity and quality. Originality/value: A new route for the fly ash use is demonstrated and this can become an unavoidable task for porous material manufacturing, a viable way to manage this industrial waste and to protect the environment.
10
EN
Purpose: At thermal power plants the fly ash (FA) is stored either through dry or wet disposal systems. These storage practices result in different features for fly ashes, such as their interaction with alkalis and hence the potential of zeolite synthesis will be different. With the aim to demonstrate this, it was conducted some investigations to study the physical, chemical, morphological and mineralogical characteristics of the fly ash residues, then were used to synthesis zeolites by a double stage fusion-hydrothermal method. Design/methodology/approach: The raw and converted fly ash samples were characterized with respect to their composition, crystallinity and morphology, by SEM and XRD analysis. The effects of environment conditions and process parameters on the zeolitization process were studied and analysed. Findings: The analysis of these residues showed that dry ash attains a high cation exchange capacity (CEC) and SiO2 /Al2O3 ratios, which is in agreement to the formation of fly ash zeolites as compared to its counterpart. The experimental results indicate that the fusion temperature does not influence on the synthesis mechanism in range of 500-800 (°C) having only an effect of acceleration. The increasing of alkaline activator/fly ash ratio enhances the zeolitization degree. Research limitations/implications: The scientific basis for the issues on the zeolitization characteristics of fly ash and its use to manufacture porous materials calls yet for further elucidation and development. Practical implications: This study helps to establish the superiority of dry ash over wet ash for synthesizing porous materials and their enhanced quantity and quality. Originality/value: A new route for the fly ash use is demonstrated and this can become an unavoidable task for porous material manufacturing, a viable way to manage this industrial waste and to protect the environment.
EN
Flower-like ZnO microstructures were successfully synthesized via a facile hydrothermal route without using any surfactants. The morphology of these microstructures can be easily controlled by adjusting the pH of the reaction solution. The possible growth mechanism of ZnO hierarchical microstructures was proposed based on the X-ray powder diffraction (XRD) and scanning electron microscope (SEM) results. The photocatalytic activity studies of ZnO nanocrystals demonstrated their excellent photocatalytic performance in degrading aqueous methylene blue (MB) under UV-A light irradiation. This higher photocatalytic activity of the ZnO nanoplates was mainly attributed to the exposed facets with the higher surface energy.
EN
In the present work, we have prepared Bi2Te3 nanostructures with different morphologies such as nano-spherical, nanoplates and nanoflakes obtained using various surfactant additions (EG, PVP, and EDTA) by a hydrothermal method. The shape of the nanoparticles can be controlled by addition of surfactants. The samples were characterized by x-ray diffraction (XRD) and scanning electron microscopy (SEM). It is found that the minority BiOCl phase disappears after maintained pH at 10 with EG as surfactant. SEM bulk microstructure reveals that the sample consists of fine and coarse grains. Temperature dependence of thermoelectric properties of the nanostructured bulk sample was investigated in the range of 300-450K. The presence of nanograins in the bulk sample exhibits a reduction of thermal conductivity and less effect on electrical conductivity. As a result, a figure of merit of the sintered bulk sample reached 0.2 at 400 K. A maximum micro Vickers hardness of 102 Hv was obtained for the nanostructured sample, which was higher than the other reported results.
13
Content available remote Preparatyka nanoproszków tytanianu baru metodą hydrotermalną
PL
W pracy badano wpływ warunków syntezy hydrotermalnej nanocząstek BaTiO3 z użyciem azotanu, chlorku lub wodorotlenku baru oraz nanoproszku tlenku tytanu w temperaturach 100-200 °C. We wszystkich badanych przypadkach rentgenowska analiza fazowa potwierdziła istnienie BaTiO3. Jednakże, morfologia proszków uzyskiwanych w odmiennych warunkach zasadniczo się różniła. W przypadku zastosowania niższych temperatur syntezy (100-150 °C) cząstki miały postać wielościanów lub kształt gwiazd. Synteza w 200 °C pozwoliła na uzyskanie sferycznych cząstek, których rozmiar i stopień aglomeracji zależały od czasu procesu oraz rodzaju zastosowanych substratów.
EN
In this work the experimental conditions for growth of BaTiO3 nanoparticles in aqueous solutions using of barium nitrate, chloride or hydroxide were studied at 100-200°C. In all of the studied cases XRD proved the existence of BaTiO3 after hydrothermal synthesis. However, the morphology of the obtained powders was different. At lower temperatures (100-150 °C) star-like or polyhedron nanoparticles were observed. Synthesis at 200 °C allowed obtaining spherical particles of size and degree of agglomeration dependent on the process time and the type of the substrates used.
EN
Different types of titanate one-dimensional nanostructured materials were synthesized and characterized using scanning and transmission electron microscopy, X-ray diffraction and Raman spectroscopy. The results presented in this work unquestionably showed dependence of morphology and structure of the titanate nanopowders on parameters of hydrothermal synthesis. It was found that nanotubes, nanowires and nanoribbons are three unavoidable kinetic products of hydrothermal reaction. Moreover, increasing temperature of reaction or hydrothermal treatment duration results in acceleration of nanotube-nanowire-nanoribbon transformation. However, the sequence of titanate morphology transformation is invariable. The detailed studies further revealed that the crystal structure of hydrothermally prepared nanotubes and nanowires are indistinguishable but the determination of the exact structure is practically impossible. Because of higher crystallinity, the structure of nanoribbons can be established. It was shown that it corresponds to the monoclinic layered trititanic acid H2Ti3O7 and is isostructural with sodium derivatives Na2-xHxTi3O7.nH2O (with x near 2).
EN
Current environmental directives to conserve resources and to divert waste streams have generated significant interest in mineral recycling. In this respect, this preliminary study has demonstrated that lithium metasilicate can be prepared by hydrothermal reaction between waste container glass and lithium hydroxide solutions at 100 °C. Minor proportions of calcium hydroxide, calcite, lithium carbonate and tobermorite were also produced during the reaction. Percentage crystallinity and proportion of lithium metasilicate in the reaction product were found to increase as functions of lithium hydroxide concentration (between 1 and 4 M). This research has also shown that the lithium metasilicate phase can take up 6.4 mmol/g of Zn2+ ions after 24 h during batch sorption. Further work to optimise the yield and to appraise the antimicrobial properties of Zn2+-bearing lithium metasilicate is now warranted.
16
Content available remote The influence of VO2(B) nanobelts on thermal decomposition of ammonium perchlorate
EN
The influence of vanadium dioxide VO2(B) on thermal decomposition of ammonium perchlorate (AP) has not been reported before. In this contribution, the effect of VO2 (B) nanobelts on the thermal decomposition of AP was investigated by the Thermo-Gravimetric Analysis and Differential Thermal Analysis (TG/DTA). VO2 (B) nanobelts were hydrothermally prepared using peroxovanadium (V) complexes, ethanol and water as starting materials. The thermal decomposition temperatures of AP in the presence of 1 wt.%, 3 wt.% and 6 wt.% of as-obtained VO2( (B) nanobelts were reduced by 39 °C, 62 °C and 74 °C, respectively. The results indicated that VO2 (B) nanobelts had a great influence on the thermal decomposition temperature of AP. Furthermore, the influence of the corresponding V2O5, which was obtained by thermal treatment of VO2 (B) nanobelts, on the thermal decomposition of AP was also investigated. The results showed that VO2 (B) nanobelts had a greater influence on the thermal decomposition temperature of AP than that of V2O5.
PL
Proces mikrofalowej syntezy solwotermalnej (Microwave Solvothermal Synthesis, MSS) jest przykładem zastosowania wspomagającego reakcje chemiczne promieniowania mikrofalowego. Grzanie mikrofalowe umożliwia precyzyjne programowanie czasu syntezy. Dzięki temu możliwe jest uzyskiwanie cząstek charakteryzujących się wąskim rozkładem wielkości oraz wysokim stopniem krystaliczności (tzn. niskim udziałem faz amorficznych). Dodatkową zaletą procesu jest znacznie niższa temperatura w porównaniu z technologiami: plazmowymi, zol żel, syntezy z fazy gazowej. W artykule przedstawiono nowe reaktory do realizacji procesów MSS. Podano przykłady syntez hydroksyapatytu, tlenku cynku i tlenku cyrkonu. Wykazano możliwość sterowania właściwościami uzyskiwanych materiałów. Reaktory typu MSS-1 i MSS-2 stwarzają możliwość przemysłowej produkcji nanocząstek.
EN
Microwave solvothermal synthesis (MSS) is an example of microwave assisted wet chemical synthesis process. Microwave heating enables a precise control of the reaction time, fast heating and reducing the thermal gradients. This results in a better crystallinity of the nanoparticles comparing to the precipitation process, and a narrow size distribution. An additional advantage is a reduced synthesis temperature, since no calcination is need. In the paper we presented two new reactors used for the MSS process. We have shown their applications in the synthesis of nanohydroksyapatite ZnO and ZrO2, as well as the enhanced control of their properties possible due to the use of microwaves. The MSS-1 and MSS-2 reactors enable industrial scale production of nanoparticles.
EN
Numerous technical, economic and societal factors limit the recycling of waste soda-lime-silica glass back into the primary production process and accordingly alternative applications for this material are sought. This study demonstrates that waste soda-lime-silica container glass is a suitable feedstock material for the production of tobermorite, a calcium silicate cation exchanger. Tobermorites were synthesised at 100 °C from stoichiometric mixtures of container glass and lime under alkaline hydrothermal conditions. Increasing concentrations of sodium hydroxide (between 1.0 M and 4.0 M) in the reaction mixture promoted the formation and crystallisation of tobermorite, and also resulted in greater fragmentation of the silicate chains along the b-axis direction. The maximum removal capacities of these tobermorite specimens for Cd2+ (441 mg g-1) and Zn2+ (122 mg g-1) compared well with those of other waste-derived sorbents. Superior Cd2+- and Zn2+-uptake capacities and kinetics were observed for the least crystalline tobermorite specimen, indicating that stacking defects facilitate the transport and exchange of cations within the lattice.
19
Content available remote Synteza zeolitów z perlitu i ich zdolności sorpcyjne
PL
W pracy przedstawiono wyniki badań nad procesem syntezy materiału zeolitowego z odpadowej frakcji pylastej powstałej przy produkcji perlitu ekspandowanego. Przeanalizowano wpływ stężenia i ilości roztworu NaOH, temperatury oraz czasu syntezy na rodzaj i ilość powstałych produktów. W zależności od warunków, w jakich prowadzony był proces, zidentyfikowane na podstawie rentgenowskiej analizy fazowej (XRD) produkty to: zeolit Na-P1, zeolit X, zeolit A oraz hydroksysodalit. Obecność faz zeolitowych potwierdziły pomiary spektroskopowe w zakresie środkowej podczerwieni oraz obserwacje w mikroskopie skaningowym. Stwierdzono, że istnieje możliwość optymalnego doboru parametrów syntezy zeolitów; już po 24 h w temperaturze przynajmniej 60 °C i przy stężeniu NaOH powyżej 3,0 mol/dm3 możliwe jest efektywne przekształcenie perlitu w materiał zeolitowy. Na podstawie analizy składu fazowego (zawartość zeolitów A oraz X) oraz mikrostruktury uzyskanych próbek wyselekcjonowano te o potencjalnie wysokich zdolnościach sorpcyjnych. Wyznaczono pojemności sorpcyjne wybranych próbek. Stwierdzono, że sodowe zeolity uzyskane w procesie syntezy z perlitu ekspandowanego mogą być z powodzeniem wykorzystywane w procesach sorpcyjnych.
EN
The paper presents research in synthesis of zeolites using waste dusty fractions coming from the production of expanded perlite. The influence of concentration and amount of a aqueous solution of NaOH together with temperature and time of synthesis on the type and quantity of the resulting products was analyzed. Depending on the process conditions, zeolite Na-P1, zeolite X, zeolite A, and hydroxysodalite were the products identified by X-ray diffraction analysis (XRD). The presence of the zeolite phases has been confirmed by mid-infrared spectroscopic measurements and scanning electron microscope observations. It has been found that it is possible to optimize the synthesis parameters. The perlite dust transforms into the zeolitic material just after 24 h synthesis in the NaOH aqueous solution of concentration above 3.0 mol/dm3 at ≥ 60 °C. Basing on the content of the A and X zeolites, and the microstructure of the obtained samples, the zeolite materials of potentially high sorption capacity were selected. Cation exchange capacities of the selected samples were determined. It has been found that sodium zeolites obtained from the perlite dust can be successfully used in sorption processes.
20
EN
Purpose: The electronic conductivity of derivatives of MgxVyOz type compounds is magnitude higher than that of the vanadium oxide without magnesium. Also, magnesium containing compounds exhibit significantly improved kinetic behaviour and rate capability. In this perspective, we aim to synthesis of magnesium vanadium oxide under mild hydrothermal conditions. Design/methodology/approach: Double phase magnesium vanadium oxides were synthesized by dissolving magnesium nitrate and V2O5 in the ultra pure water with in an appropriate molar ratio. The homogeneous solution in the stainless-steel container was put into furnace and heated 3 days (72 hours) at 180ºC. The product was washed by high pure water and ethanol, dried at 70ºC for 2 hours and homogenized in an agate mortar. Then, final product was ready to analyse. Powder X-ray Diffractometer (XRD) was used to determine crystal structure of the product. FTIR spectrum was taken to support the functional groups. Thermo gravimetric-differential thermal analysis (TG/DTA) was carried out to identify thermal character. Morphological properties and semi-quantitative analyse of the sample was performed by Scanning electron microscope/Electron disperse (SEM/EDX). Phase analyse was realized by High Score Plus Program. Findings:The XRD patterns show that the product is Mg0.01V2O5 (ICDD:89-0610)-β-Mg1.9V3O8 (ICDD:23-1232). The result of phase analyse show that the sample contains %27.2 Mg0.01V2O5 and %72.8 β-Mg1.9V3O8. The mixture was obtained under mild hydrothermal conditions for the first time as distinct from literature. Characterization studies were mainly based on powder X-ray diffraction technique. Also, thermal behaviour, morphology and percentage of component were determined. Research limitations/implications:The principal of hydrothermal method is low temperature/high pressure synthesis in water. Sometimes, optimizing of the most convenient condition can be time and chemical consuming. This situation could be a limit to use hydrothermal method. But, this can eliminate with deep background. Practical implications: The compounds can find many application areas utilizing kinetic behaviour, rate capability and electronic conductivity properties. Originality/value: We achieved the hydrothermal synthesis of Mg0.01V2O5 (ICDD:89-0610)- β-Mg1.9V3O8 (ICDD:23-1232) under mild hydrothermal conditions for the first time as distinct from literature.
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