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1

Effect of surfactant concentration in modifying solution on corrosion properties of the coatings based on vinyltrimethoxysilane (VTMS) and poly(3,4-ethylenedioxythiophene) (PEDOT)

Kucharczyk A., Adamczyk Lidia, Miecznikowski K.

Archives of Materials Science and Engineering

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2023

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Vol. 121, nr 1

5--17

EN

Purpose: This paper presents an analysis of the structure and physicochemical properties of coatings based on an organofunctional silane (VTMS), a conductive polymer (PEDOT), and a surfactant (polyoxyethylene glycol monolauryl ether BRIJ). Design/methodology/approach The coatings were deposited on X20Cr13 stainless steel and glassy carbon specimens using sol-gel immersion. The obtained coatings were characterised in terms of topography, microstructure, roughness, adhesion to the steel substrate, thickness, and corrosion resistance. Corrosion tests were conducted in sulfate environments with pH = 2 without or with the addition of Cl- ions. Findings: The use of different surfactant concentrations in the modifying solution is intended to improve the deposition efficiency and increase the degree of dispersion of silane and conducting polymer. Research limitations/implications The tested coatings were found to slow down the corrosion of the steel substrate, thus effectively protecting it from this phenomenon. The use of a surfactant compound is intended to increase the degree of dispersion of silane and polymer in the modifying solution to improve deposition efficiency. Practical implications: Test carried out in corrosive media have shown that the coatings proposed in the above work, based on VTMS silane, PEDOT polymer and BRIJ surfactant, significantly increase the corrosion resistance of the tested materials, which confirms their effectiveness and possibility of application in various industries. Originality/value: The novelty of this paper is the use of silane (VTMS), polymer (PEDOT) and surfactant (BRIJ) as components of the anticorrosion coating.

2

Effect of electrochemical treatment in eutectic solvent and deposition of SiO2 sol-gel coating on corrosion resistance of 316L steel in Ringer’s solution

Mazur-Nowacka Anna, Marczewski Marek, Tylus Włodzimierz, Szczygieł Bogdan, Chęcmanowski Jacek

Ochrona przed Korozją

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2022

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nr 5

152--156

EN

The 316L stainless steel samples were subjected to anodic polarization in a eutectic solvent and then theSiO2 coatings were deposited on them using the sol-gel method. The coatings were prepared from a sol containing TEOS as a precursor and ethanol as a solvent. The obtained samples were exposed in Ringer’s solution. Studies have shown that electrochemical treatment of 316L steel affects both the morphology, topography and roughness of the metallic material. Potentiodynamic tests showed that the best barrier properties after exposure to Ringer’s solution were obtained for 316L steel subjected to electrochemical treatment, additionally covered with a SiO2 coating. The deposition of the three-layer SiO2 coatings reduces the corrosion current density and an increase in the polarization resistance relative to the uncoated 316L steel.

PL

Próbki ze stali nierdzewnej 316L poddano polaryzacji anodowej w rozpuszczalniku eutektycznym, a następnie metodą zol-żel osadzono na nich powłoki SiO2. Powłoki otrzymywano z zolu zawierającego TEOS jako prekursor i etanol jako rozpuszczalnik. Otrzymane próbki eksponowano w roztworze Ringera. Badania dowiodły, że elektrochemiczna obróbka stali 316L wpływa zarówno na morfologię oraz topografię, jak i chropowatość materiału metalicznego. Potencjodynamiczne badania wykazały, że najlepsze właściwości barierowe po ekspozycji w roztworze Ringera uzyskano dla stali 316L poddanej obróbce elektrochemicznej i dodatkowo pokrytej powłoką SiO2. Osadzenie trójwarstwowych powłok SiO2 powoduje zmniejszenie gęstości prądu korozji oraz wzrost oporu polaryzacji względem niepokrytej stali 316L.

3

Powłoki o właściwościach samoczyszczących aplikowane na materiały tekstylne

Masłowska-Lipowicz Iwona, Słubik Anna, Wyrębska Łucja

Technologia i Jakość Wyrobów

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2021

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R. 66

124--133

PL

Właściwości samoczyszczące powierzchni cieszą się dużym zainteresowaniem ze względu na szerokie możliwości ich zastosowań w różnych gałęziach przemysłu (tekstylia, budownictwo, urządzenia sanitarne, części samochodowe, panele fotowoltaiczne, urządzenia elektroniczne, lotnictwo, kosmonautyka i in.). Powierzchnie samoczyszczące mogą mieć właściwości hydrofobowe lub hydrofilowe. Samoczyszczące tekstylia umożliwiają oszczędzanie wody, środków piorących, energii i czasu. Ponadto, są odporne na przenikanie wody i kumulowanie zanieczyszczeń na ich powierzchni. Opracowano metodę modyfikacji tkaniny bawełnianej w celu nadania jej właściwości samoczyszczących. Metoda ta opiera się na aplikacji poli(dimetylosiloksanu) oraz nanometrycznego dwutlenku tytanu na tkaninę bawełnianą.

EN

Self-cleaning properties of surfaces are of great interest due to the wide range of their applications in various industries (textiles, construction, sanitary equipment, automotive parts, photovoltaic panels, electronic devices, aviation, aerospace, etc.). Self-cleaning surfaces can have hydrophobic or hydrophilic properties. Self-cleaning textiles allow saving water, detergents, energy and time. Moreover, they are resistant to water penetration and accumulation of contaminants on their surface A method of modifying cotton fabric in order to make it self-cleaning has been developed. This method is based on the application of poly(dimethylsiloxane) with terminal hydroxyl groups and nanometric titanium dioxide to cotton fabric.

4

Właściwości odbiciowe struktur z warstwami wytwarzanymi metodą zol-żel i techniką dip-coating

Gajda Aleksandra, Gondek Ewa, Karasiński Paweł

Prace Instytutu Mechaniki Górotworu PAN

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2021

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T. 23, nr 1-4

35--43

PL

Artykuł prezentuje wyniki badań właściwości odbiciowych struktur z cienkimi warstwami krzemionkowymi, z warstwami ditlenku tytanu TiO2 oraz z warstwami kompozytowymi SiO2:TiO2, które wytworzone zostały za pomocą metody zol-żel i techniki dip-coating na dwóch różnych rodzajach podłoży. W badaniach zastosowano podłoża ze szkła sodowo-wapniowego (podłożowe płytki mikroskopowe) oraz wafle krzemowe. Na szkle sodowo-wapniowym wytworzone były warstwy kompaktowej krzemionki, dla której współczynnik załamania wynosił ~1,45 oraz warstwy porowatej krzemionki o współczynniku załamania ~1,2 i porowatości wynoszącej w przybliżeniu 50%, a także warstwy dwuskładnikowe SiO2:TiO2 o homogeniczności na poziomie cząsteczkowym. Na podłożach krzemowych wytworzone zostały struktury antyrefleksyjne jedno- oraz dwuwarstwowa. Wykorzystując spektrofotometr światłowodowy wyznaczono charakterystyki odbiciowe badanych struktur w zakresie widmowym 200-1000 nm. Na podstawie wykonanych pomiarów określono wpływ rodzaju podłoża i ilości naniesionych warstw na charakterystyki odbiciowe. Porównując charakterystyki odbiciowe badanych struktur warstwowych z charakterystykami odbiciowymi podłoży określono jednorodność optyczną warstw.

EN

The article presents the results of investigations of reflectance properties of structures with silica, titanium dioxide TiO2 and SiO2:TiO2 composite thin films, which were fabricated by sol-gel and dip-coating techniques on two different types of substrates. Soda-lime glass substrates (substrate microscope plates) and silicon wafers were used in this study. Compact silica layers were produced on soda-lime glass for which the refractive index was about 1.45 and porous silica layers with a refractive index of about 1.2 and a porosity of approximately 50%, as well as SiO2:TiO2 binary layers with homogeneity at the molecular level. Single- and double-layer antireflective structures were fabricated on silicon substrates. Using a fiber optic spectrophotometer, the reflectance characteristics of the structures studied were determined in the spectral range 200-1000 nm. The influence of the substrate type and the number of applied layers on the reflectance characteristics was determined on the basis of the performed measurements. By comparing the reflectance characteristics of the investigated layered structures with the reflectance characteristics of the substrates, the optical homogeneity of the layers was determined.

5

Improvement of the Properties of Ti6Al7Nb Titanium Alloy in Terms of the Type of Surface Modification

Woźniak A., Bialas O., Adamiak M.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 2

735--741

EN

The paper presents the influence of ZrO2 coating on Ti6Al7Nb titanium alloy depending on the method of deposition. The coatings were made by sol-gel method and atomic layer deposition (ALD). Wettability tests, pitting corrosion assessment and electrochemical impedance spectroscopy (EIS) were carried out in the paper. Complementary macro- and microscopic observations, roughness analysis by profilometric method and atomic force microscopy (AFM) were made. Based on the results obtained, it can be concluded that the type of method of depositing the layer on the surface of the material has a significant influence on its properties and that it should be taken into account during the process of the material improvement. Drawing on the findings presented, it can be inferred that roughness has a significant impact upon the surface wetttability of the tested surfaces and their related corrosion resistance. The obtainment of hydrophobic surfaces is for smaller rougidity values.

6

Surface properties of the doped silica hydrophobic coatings deposited on plasma activated glass supports

Chodkowski Michał, Terpiłowski Konrad, Goncharuk Olena

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 6

1450--1459

EN

The paper discusses preparation and characteristics of silica hydrophobic layers deposited on the plasma-modified glass supports. The surfaces were investigated using wettability measurements, profilometry, photoacoustic and infrared spectroscopy, X-ray photoelectron spectroscopy as well as scanning electron microscopy. The wettability measurements showed that the obtained surfaces are hydrophobic – the water contact angle was in the range of 140-150 degrees. The photoacoustic and infrared spectroscopy as well as X-ray photoelectron spectroscopy disclosed the surface compositions, particularly that of the hydrophobic alkyl groups deposited on them. They were methyl groups introduced during hydrophobization by hexamethyldisilazane. In addition, it was found that the number of groups on the surface depends on the kind of plasma by which the supports were activated. The optical profilometer showed differences in the surface roughness which affects their hydrophobicity. Moreover, the surface free energies were determined using the contact angle hysteresis method. They disclosed differences in each surface, depending on the way of supports activation. The largest hydrophobicity was obtained on the layer deposited on the support activated by the argon plasma. However, support activation by the air plasma resulted in a decrease of hydrophobicity compared to that of the non-activated surface.

7

Fabrication of fluoride nanocrystals and their spectroscopic properties

Pawlik N., Szpikowska-Sroka B., Goryczka T., Pisarski W. A.

Optica Applicata

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2019

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Vol. 49, nr 3

415--426

EN

In this work, the fabrication of glass-ceramic materials containing MF3:Eu3++ (M = La, Gd) nanocrystals dispersed in silica sol-gel hosts has been presented. The transformation from liquid sols towards bulk samples was also examined based on IR measurements. The crystallization temperatures and formation of MF3 phases were verified based on TG/DSC analysis and XRD measurements. The optical properties of prepared Eu3+5D05D0 → 7FJ (J = 1–4) emission bands, which were recorded within the reddish-orange spectral area under near-UV illumination (λexc = 393 nm). Recorded luminescence spectra and double-exponential character of decay curves for prepared glass-ceramic samples indicated the successful migration of Eu3+ dopant ions from amorphous silica framework to low-phonon energy MF3 nanocrystal phases.

8

Synthesis and characterization of binary and ternary nanocomposites based on TiO2, SiO2 and ZnO with PVA based template-free gel combustion method

Fakoori Elham, Karami Hassan, Nezhadali Azizollah

Materials Science Poland

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2019

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Vol. 37, No. 3

426--436

EN

Binary and ternary nanocomposites based on TiO2, SiO2 and ZnO were synthesized by PVA-based template-free gel combustion method. The morphology and the particles sizes of the synthesized samples depended on some parameters including the initial concentrations of metal salts and PVA amount in the sol, solvent composition and solution pH. Effects of these parameters were investigated and optimized by using the Taguchi method. In the experimental design, the Taguchi L25 array was used to investigate six factors at five levels. The samples were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), Brunauer-Emmett-Teller (BET) specific surface areas, scanning electron microscopy (SEM). The obtained results showed that the present method can be used to synthesize TiO2/SiO2/ZnO ternary nanocomposite with an effective surface area of 0.3 m2 · g−1 and ZnO/TiO2, TiO2/SiO2, ZnO/SiO2 binary nanocomposites with an effective surface area of 234 m2 · g-1, 6 m2 · g-1 and 0.5 m2 · g-1, respectively. The ZnO/TiO2 nanocomposite which was synthesized under the following experimental conditions: 2.5 wt.% Zn salt, 2.5 wt.% Ti salt, 2.0 wt.% PVA, pH = 1 and ethanol:water ratio 30:70 was selected by the Taguchi method as an optimum sample with the smallest particles (average diameter = 50 nm).

9

Determination of growth kinetics and size dependent structural, morphological, optical characteristics of sol-gel derived silica nanoparticles in silica matrix

Uysal Bengü Özuğur, Tepehan Fatma Z.

Materials Science Poland

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2019

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Vol. 37, No. 1

16--24

EN

Nanocomposite silica thin films made using the sol-gel method were studied. The nano-silica films were prepared using a mixture of tetraethyl orthosilicate (TEOS), deionized water, ethanol, and ammonia solution. To control the growth of the particles inside the film, the nanocomposite silica film was prepared using a mixture of the nano-silica sol and the silica sol. The change in the particle size with the heat treatment temperature ranging from 450 °C to 1100 °C was investigated. X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), NKD (refractive index-N, extinction coefficient-K, and thickness-D) and ultraviolet-visible (UV-Vis) spectrophotometry were used for characterization purposes. The XRD studies showed that the nano-silica thin films were amorphous at all annealing temperatures except for 1100 °C. The α-cristobalite crystal structure formed at the annealing temperature of 1100 °C. Optical parameters, such as refractive indices and extinction coefficients, were obtained using the NKD analyzer with respect to the annealing temperature of the films. The activation energy and enthalpy of the nanocomposite silica film were evaluated as 22.3 kJ/mol and 14.7 kJ/mol, respectively. The cut-off wavelength values were calculated by means of extrapolation of the absorbance spectra estimated using the UV-Vis spectroscopy measurements. A red shift in the absorption threshold of the nanocomposite silica films indicated that the size of the silica nanoparticles increased with an increase of the annealing temperatures from 450 °C to 900 °C, and this confirms the quantum confinement effect in the nanoparticles.

10

Synthesis and structural characterization of niobium-doped hydroxyapatite ceramics

Korzeniewski Wojciech, Witkowska Agnieszka

Engineering of Biomaterials

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2019

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Vol. 22, no. 150

10--15

EN

Hydroxyapatite (HAp) ceramic materials are consi-dered as one of the most promising implant materials in bone surgery and in dentistry. They exhibit unique biocompatibility, bioactivity, and osteoconductivity, which are the most desirable biomaterial features. However, HAp itself is brittle, has low strength, high degree of crystallinity and low solubility at physiological pH. Doping synthetic HAp with metal ions plays an important role in improving its structural and physico--chemical properties. HAp doped with niobium ions has not been widely investigated so far. However, the results of studies available in the literature show that the synthesized CaO-P2O5-Nb2O5 compounds still show good biocompatibility, very low cytotoxicity and, additionally, they stimulate osteoblast proliferation. Therefore, this study is dedicated to the niobium--doped HAp ceramics obtained by two methods: mechano-chemical synthesis and sol-gel method. Bioceramics chemical composition, morphology, and structure were characterized by means of scanning electron microscopy imaging, BET method, X-ray diffraction, Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The results indicate that nanoceramics of non-stoichiometric HAp with a clear Ca deficiency on the nanograin surface were obtained. Moreover, it has been observed that the presence of Nb dopants and the synthesis method directly affect unit cell parameters, crystallinity degree, crystallites size, porosity and distribution of niobium in the grain structure. Mechano-chemical synthesis has allowed effective niobium incorporation into the HAp structure, leading to the quite homogeneous Nb distribution in the grain volume. Whereas, Nb-doping by sol-gel method has led to dopants location mainly on the grain surface.

11

Synthesis and characterization of TiO2 thin film on fly ash cenospheres

Szołdra Paulina, Pichór Waldemar, Cholewa-Kowalska Katarzyna, Adamczyk Anna, Szudek Wojciech

Composites Theory and Practice

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2019

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R. 19, nr 2

71--75

EN

Titanium dioxide (TiO2) thin films obtained on quartz glass and fly ash cenospheres were studied. Titanium(IV) butoxide (Ti(OBu)4), diethanoloamine (DEA), ethanol and deionized water were used as the starting materials. A layer of TiO2 nanoparticles was coated on the surface of the substrates using the sol-gel method. The thickness of the TiO2 coatings and the influence of the annealing temperature on the formation of TiO2 crystallites were studied. The dried gels were treated for 90 min in the temperature range of 400÷640°C to obtain crystallized anatase and rutile. Additional nanopowder TiO2 samples were prepared and their crystallinity was determined using X-ray diffraction (XRD). It was successfully shown that the anatase crystalline phase is formed when the TiO2 gel is heated to 480°C, while the rutile phase is obtained at 640°C. Changes in film thickness were studied using an atomic force microscope (AFM). The profound effect of gel viscosity on the thickness of the film was noticed. UV-Vis absorption spectroscopy, performed on the sample treated at 480°C (containing anatase phase only), showed strong ultraviolet light absorption below 400 nm. The estimated band-gap value was 3.2 eV. Transmission scanning microscopy (TEM) examination of the powders revealed agglomerated nanoparticles. A uniform, continuous layer on the surface of the treated microspheres was observed under a scanning electron microscope (SEM). The study shows that the annealing temperature has a profound effect on the phase composition and crystallite size of the sol-gel synthesized TiO2 nanopowders.

PL

Badaniom poddano warstwy z dwutlenku tytanu (TiO2), które zostały osadzone na powierzchni szkła kwarcowego i mikrosfer z popiołów lotnych. Wyjściowymi substratami były butanolan tytanu(IV) (Ti(OBu)4), dietanoloamina (DEA), etanol i woda dejonizowana. Warstwy z nanocząstkami TiO2 przygotowano, wykorzystując metodę zol-żel. Zbadano grubość otrzymanych warstw oraz wpływ temperatury wypalania na powstawanie krystalitów TiO2 syntetyzowanych w zol-żelu. Wysuszone żele poddano obróbce termicznej w zakresie temperatur 400÷640°C przez 90 minut w celu uzyskania krystalicznych form anatazu i rutylu. Za pomocą dyfrakcji rentgenowskiej (XRD) określono skład fazowy nanoproszków TiO2. Udało się wykazać, że krystaliczny anataz otrzymywany jest podczas ogrzewania żelu w temperaturze 480°C, natomiast krystaliczna faza rutylowa w 640°C. Zmianę grubości warstwy obserwowano z wykorzystaniem mikroskopu sił atomowych (AFM). Zaobserwowano duży wpływ lepkości zolu na grubość otrzymywanych powłok. Przeprowadzona przy użyciu spektroskopii absorpcyjnej UV-Vis analiza próbki poddanej obróbce termicznej w 480°C (w której jedyną występującą fazą był anataz) wykazała silną absorpcję promieniowania ultrafioletowego o długości fali poniżej 400 nm. Szacowana wartość energii pasma wzbronionego wynosiła 3,2 eV. Obrazy z transmisyjnego mikroskopu skaningowego (TEM) ukazały zaglomerowane nanocząstki, a obrazy ze skaningowego mikroskopu elektronowego (SEM) pokazały jednorodną warstwę na mikrosferach. Wykonane badania pokazują, że temperatura wypalania ma ogromny wpływ na skład fazowy i rozmiar krystalitów nanoproszków TiO2 syntetyzowanych metodą zol-żel.

12

Synthesis and properties of TiO2, NiO and ZnO nanoparticles and their possible biomedical application

Szmajnta K., Szindler M.

Archives of Materials Science and Engineering

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2019

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Vol. 98, nr 2

81--84

EN

Purpose: The main purpose of this publication is to bring closer method of synthesis and examining basic properties of TiO2, ZnO and NiO nanoparticles (NPs), and investigate their possible biomedical application. Design/methodology/approach: Nanopowders were made with sol-gel method. Surface morphology studies of the obtained materials were made using Zeiss's Supra 35 scanning electron microscope and the structure using S/TEM TITAN 80-300 transmission electron microscope. In order to confirm the chemical composition of observed nanopowders, qualitative tests were performed by means of spectroscopy of scattered X-ray energy using the Energy Dispersive Spectrometer (EDS). The DLS (Dynamic Light Scattering) method was used to analyse the particle size distribution using the AntonPaar Litesizer 500 nanoparticle size analyser. Changes in particle size distribution at elevated temperatures were also observed. The TiO2, ZnO and NiO NPs with spherical shape were successfully produced by sol-gel method. Findings: The diameter of the as prepared nanoparticles does not exceed 25 nm which is confirmed by the TEM analysis. The highest proportion among the agglomerates of the nanoparticles has been shown to show those with a diameter of 80 to 125 nm. The qualitative analysis of EDS confirmed the chemical composition of the material. Practical implications: Nanoparticles (NPs) has been receiving an incrementally increasing interest within biomedical fields researchers. Nanoparticles properties (physical, chemical, mechanical, optical, electrical, magnetic, etc.) are different from the properties of their counterparts with a larger particle size. Originality/value: The nanoparticles were prepared using sol-gel method which allows the particle size to be controlled in a simple way.

13

Correlation between structural, magnetic and spectroscopic properties of Mg substituted CoFe2O4

Nethala G. P., Tadi R., Anupama A. V., Shinde S. L., Veeraiah V.

Materials Science Poland

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2018

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Vol. 36, No. 2

310--319

EN

Mg substituted cobalt ferrite spinel powder samples with the general formula MgxCo1 – xFe2O4 (x = 0 to 0.25) were synthesized chemically through sol-gel method and annealed at 1100 °C for 2 h. They were initially screened for the structural and morphological properties by X-ray diffraction and field emission scanning electron microscopy, respectively. Vibrational properties of the samples were studied by Raman and infrared spectroscopies. X-ray diffraction confirmed the formation of single pure or near-pure phase with cubic spinel structure for all the samples with expected occupancy values. The field emission scanning electron microscopy revealed a decrease in the particle size with an increase in Mg concentration. Both structural and magnetic properties of the samples were characterized using Mössbauer spectroscopy while the magnetic properties were studied using vibrating sample magnetometry. The changes in magnetic moment of ions, their coupling with neighboring ions and cation exchange interactions were confirmed from the Mössbauer spectroscopy analysis. Saturation magnetization and coercivity values can be explained based on the Slater-Pauling curve. The magnetometry results showed a decrease in saturation magnetization of the samples with increase in Mg concentration.

14

Study on Crystal Structure and Magnetic Properties of Ba4Co2Fe36O60 by Sol-Gel Method

Jeong K.-P., Yang S.-W., Kim J.-G.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 3

1449--1452

EN

U-type ferrite typified by Ba4Co2Fe36O60 is used as a RAM (Radar Absorbing Materials) in the X-band (8-12 GHz). Ba4Co2Fe36O60 is known to have a complex crystal structure, which makes it difficult to obtain single phase and have low reproducibility. Previously known U-type ferrites have been fabricated based on a ceramic process that mixing (by a ball mill), calcining, grinding, binder mixing, drying, sieving, pressing and sintering. In contrast, the process of preparing the powder by the sol-gel method and its heat-treating is advantageous in that it can reduce the process steps and the required time. In addition, the precise stoichiometric control by the sol-gel method can effectively evaluate the effect of added or substituted elements. In this study investigates the crystal structure of Ba4Co2Fe36O60 synthesized by the sol-gel method and the morphology of U-type ferrite nano-powders according to various heat treatment conditions. Analysis of the crystal structure is used for XRD. Morphology and size are observed by SEM. In addition, VSM is performed to confirm the change of magnetic properties according to various heat treatment conditions.

15

Oily wastewater treatment using a zirconia ceramic membrane : a literature review

Kwaśny J. A., Kryłów M., Balcerzak W.

Archives of Environmental Protection

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2018

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Vol. 44, no. 3

3--10

EN

The goal of this article was to review the literature which discusses the problem of oily wastewater purification by membrane filtration. The authors focused on membranes containing zirconium compounds, mainly ZrO2, used in pressure driven membrane processes. The efficiency of the oil removal processes for various membranes (ceramic and composite), usually above 95% for the oil contaminated sewage, was compared. The influence of zirconium compounds on the properties of ceramic membranes was also discussed. The methods of producing ceramic membranes have been briefly characterized as well. Ceramic membranes are usually obtained by sol-gel technique but also by isostatic compression, reverse phase technique, or hydrothermal crystallization. Ceramic membranes are formed with zirconia, which cause an increase in filtration efficiency by improvement of hydrophilic properties of the membrane. Moreover, the addition of ZrO2 results in increased chemical and hydrothermal membrane stability. The efficiency of the filtration processes using the presented membranes was high, suggesting that membrane filtration processes are highly effective purification methods.

PL

Artykuł stanowi przegląd literatury, w którym omówiono problem oczyszczania ścieków olejowych w oparciu o filtrację membranową. Skupiono się na membranach ciśnieniowych zawierających związki cyrkonu, głównie ZrO2. Porównano skuteczność procesów oczyszczania dla różnych membran (ceramicznych i kompozytowych). Omówiono wpływ związków cyrkonu na właściwości użytkowe membran ciśnieniowych. Membrany ceramiczne są zwykle uzyskiwane za pomocą techniki zol-żel, ale również przez prasowanie izostatyczne, technikę odwróconej fazy lub krystalizację hydrotermiczną. Membrany ceramiczne są formowane z tlenkiem cyrkonu, co skutkuje wzrostem skuteczności filtracji.

16

Wpływ cienkich warstw SiO₂ osadzonych metodą zol-żel na stali 316L na jej odporność korozyjną i bioaktywność w roztworze sztucznej krwi

Mazur A., Chęcmanowski J. G., Szczygieł B.

Przemysł Chemiczny

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2017

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T. 96, nr 5

1183--1188

PL

Metodą zol-żel nanoszono powłoki SiO₂ na podłoże ze stali nierdzewnej 316L w celu poprawy bioaktywności oraz odporności korozyjnej materiału. Powłoki otrzymywano z zolu zawierającego tetraetoksysilan (jako prekursor) oraz alkohol izopropylowy lub alkohol butylowy jako rozpuszczalnik. Próbki eksponowano w roztworze sztucznej krwi (SBF) przez 142 doby. Badania SEM i EDS wykazały, że wielowarstwowe powłoki SiO₂ uzyskane z zolu zawierającego izopropanol sprzyjają tworzeniu ceramiki apatytowej, co może świadczyć o ich bioaktywności. Zgodnie z wynikami badań potencjodynamicznych i ICP odporność korozyjna stali w roztworze SBF wzrasta po osadzeniu powłok SiO₂ metodą zol-żel.

EN

Single and multilayer SiO₂ coatings were deposited on 316L steel from (EtO) ₄Si-contg. iso-PrOH or BuOH solutions and immersed in artificial blood soln. for 142 days. The sample surfaces were studied by energy-dispersive spectroscopy. Iso-PrOH was a more efficient solvent than BuOH in generating the layer bioactivity. The corrosion resistance of the coating increased with increasing no. of layers.

17

Właściwości ochronne zol-żelowych powłok ZrO2 na stali 316L w roztworze sztucznej krwi

Mazur A., Chęcmanowski J., Szczygieł B.

Ochrona przed Korozją

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2017

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nr 5

146--151

PL

Metodą zol-żel nanoszono powłoki ZrO2 na podłoże ze stali nierdzewnej 316L. Powłoki otrzymywano z zolu zawierającego jako prekursor tetraetoksycyrkonian i butanol jako rozpuszczalnik. Otrzymane próbki eksponowano w roztworze sztucznej krwi (SBF) przez 120 doby. Badania potencjodynamiczne wykazały, że osadzenie pięciowarstwowych powłok ZrO2 powoduje dwukrotny wzrost odporności korozyjnej stali w czasie długoterminowej ekspozycji w roztworze SBF. Zgodnie z wynikami badań SEM i EDS wykazano, że na powierzchni cienkich warstw ZrO2 przyrasta ceramika apatytowa.

EN

ZrO2 coatings were sol-gel deposited on a base made of stainless steel 316L. The sol used for this purpose contained zirconium(IV) ethoxide (ZrEt) as the precursor and butanol as the solvent. The obtained samples were exposed to simulated body fluid (SBF) for 120 days. Potentiodynamic tests showed that the deposition of five-layer ZrO2 coatings results in a twofold increase in the corrosion resistance of the steel during long-term exposure to SBF. The results of SEM and EDS analyses demonstrated that apatite ceramic accretes on the surface of the thin ZrO2 layers.

18

Technologia i podstawowe właściwości wieloskładnikowej ceramiki na bazie Pb(Zr0,75Ti0,25)O3 syntezowanej metodą zol-żel

Bochenek D., Niemiec P., Osiński M.

Materiały Ceramiczne

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2017

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T. 69, nr 2

90--96

PL

Celem pracy było otrzymanie wieloskładnikowej ceramiki typu PZT domieszkowanej chromem, tantalem i manganem, wykorzystując mokrą metodę chemiczną zol-żelową. Proces technologiczny otrzymywania ceramiki składał się z kilku etapów. W pierwszym etapie ceramiczny proszek o składzie Pb(Zr0,75Ti0,25)O3 otrzymano w wyniku syntezy zol–żelowej, a następnie w drugim etapie do bazowego składu wprowadzono domieszki w postaci tlenków chromu (w ilości 0,15% wag.), tantalu (w ilości 0,03% wag.) oraz manganu (w ilościach 0,5% wag. lub 1,0% wag.). Syntezowanie poszczególnych składników przeprowadzono metodą reakcji w fazie stałej, natomiast spiekanie zsyntezowanego materiału przeprowadzono dwiema metodami zagęszczania: spiekaniem swobodnym (FS) i metodą jednoosiowego prasowania na gorąco (HUP). Przeprowadzono badania mikrostrukturalne, rentgenowskie, homogeniczności składu (EDS) oraz podstawowych właściwości ferroelektrycznych i dielektrycznych. Badania wykazały, że wielopierwiastkowe modyfikowanie podstawowego składu Pb(Zr0,75Ti0,25)O3 domieszkami tlenków chromu, tantalu i manganu poprawia parametry użytkowe otrzymanych materiałów. Natomiast zastosowanie w procesie technologicznym metody jednoosiowego prasowania na gorąco (HUP) pozwala uzyskać próbki o jednorodnej drobnoziarnistej mikrostrukturze z większymi wartościami maksymalnej przenikalności elektrycznej. Wieloskładnikowe materiały typu PZT o tego typu właściwościach mogą znaleźć zastosowania w mikroelektronice i mikromechatronice do budowy wysokoczęstotliwościowych przetworników piezoelektrycznych.

EN

The aim of this work was to obtain multicomponent PZT-type ceramics doped with chromium, tantalum and manganese oxides. A technological process of obtaining the ceramics consisted of several stages. In the first step, the Pb(Zr0.75Ti0.25)O3 ceramic powder was synthesized by a sol-gel method, and in the second one, an admixture of chromium (0.15 wt.%), tantalum (0.03 wt.%) and manganese (0.5 wt.% or 1.0 wt.%) oxides was introduced to the base composition. The synthesis of individual components was performed by a solid phase reaction, and the sintering process was carried out by two methods: free sintering (FS) and hot uniaxial pressing (HUP). Microstructural studies, X-ray diffraction phase analysis, studies of the material homogeneity (EDS), and the basic ferroelectric and dielectric properties were carried out. The studies have shown that the multi-elemental modification of the basic composition of Pb(Zr0.75Ti0.25)O3 by the admixtures of chromium, tantalum and manganese oxides improve the performance of the obtained ceramics. The application of the hot uniaxial pressing method (HUP) in the technological process allows obtaining a sample with the homogeneous fine-grained microstructure and higher values of the maximum dielectric permittivity. The multicomponent PZT-based materials with that type of properties can be used in microelectronics and micromechatronics to build high-frequency piezoelectric transducers.

19

Fabrication and Crystal Structure of Sol-Gel Deposited BST thin Films with Compositional Gradient

Czekaj D., Lisińska-Czekaj A., Plewa J.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2A

673--678

EN

In the present research technology of compositionally graded barium strontium titanate Ba1-xSrxTiO3 thin films deposited on stainless steel substrates by sol-gel spin coating followed with thermal annealing at T = 650°C is reported. Results of thermal behavior of the sol-gel derived powders with compositions used for fabrication of graded structure (i.e. with Sr mole fraction x =0.5, 0.4 and 0.3) are described. X-ray diffraction studies of the phase composition and crystal structure of such complex thin film configuration are given. It was found that gel powders exhibited a large total weight loss of about Δm ≈ 44-47%. Three stages of weight loss took place at temperature ranges: below T ≈ 300°C, at ΔT ≈ 300-500°C and between T = 600°C and T = 800°C. Phase analysis has shown that the dominating phase is Ba0.67Sr0.33TiO3 compound while the second phase is Ba0.7Sr0.3TiO3 or Ba0.5Sr0.5TiO3 for “up-graded” and “down-graded” structure, respectively.

20

Study on the activity of ZnO-SnO2 nanocomposite against bacteria and fungi

Omar K., Meena B. I., Muhammed S. A.

Physicochemical Problems of Mineral Processing

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2016

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Vol. 52, iss. 2

754--766

EN

ZnO-SnO2 nanocomposite was prepared by the sol-gel method. The as-prepared nanocomposite was characterized by X-ray diffraction (XRD), scanning electron micrograph (SEM-EDX), FTIR and UV-Visible spectrometer analysis techniques. The average particle size of nanocomposite was calculated from the XRD study. The average particle size of the prepared nanocomposite was 22 nm. According to the UV-Visible spectrum, the band gap value of 5.06 eV was obtained for the ZnO-SnO2nanocomposite. From the analysis techniques it was found that the metal oxides of ZnO-SnO2 mainly consist of ZnO and SnO2 metal oxides. The antibacterial and antifungal activities of the ZnO-SnO2nanocomposite were studied against Staphylococcus aureus (ATCC25923), Listeria monocytogenes (ATCC 11994)(Gram-positive), Salmonella typhi (ATCC14028), Escherichia coli (ATCC 25922)Gram-negative), Candida albicans (ATCC10231), and Aspergillus niger (ATCC 16404) (fungi)by two methods through the turbidity method or reading optical density and inhibition zone, which were carried out in the absence of irradiation. We observed an effective antibacterial and antifungal activity of the ZnO-SnO2 nanocomposite against bacteria and fungi.