Sol–Gel Synthesis and Characterization of Coatings of Mg-Al Layered Double Hydroxides

In this study, new synthetic approaches for the preparation of thin films of Mg-Al layered double hydroxides (LDHs) have been developed. The LDHs were fabricated by reconstruction of mixed-metal oxides (MMOs) in deionized water. The MMOs were obtained by calcination of the precursor gels. Thin films of sol–gel-derived Mg-Al LDHs were deposited on silicon and stainless-steel substrates using the dip-coating technique by a single dipping process, and the deposited film was dried before the new layer was added. Each layer in the preparation of the Mg-Al LDH multilayers was separately annealed at 70 °C or 300 °C in air. Fabricated Mg-Al LDH coatings were characterized by X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and atomic force microscopy (AFM). It was discovered that the diffraction lines of Mg3Al LDH thin films are sharper and more intensive in the sample obtained on the silicon substrate, confirming a higher crystallinity of synthesized Mg3Al LDH. However, in both cases the single-phase crystalline Mg-Al LDHs have formed. To enhance the sol–gel processing, the viscosity of the precursor gel was increased by adding polyvinyl alcohol (PVA) solution. The LDH coatings could be used to protect different substrates from corrosion, as catalyst supports, and as drug-delivery systems in medicine.

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Aqueous Sol-Gel Synthesis of Different Iron Ferrites: From 3D to 2D

Materials ◽

10.3390/ma14061554 ◽

2021 ◽

Vol 14 (6) ◽

pp. 1554

Author(s):

Justinas Januskevicius ◽

Zivile Stankeviciute ◽

Dalis Baltrunas ◽

Kęstutis Mažeika ◽

Aldona Beganskiene ◽

...

Keyword(s):

Magnetic Measurements ◽

Substrate Surface ◽

Sol Gel ◽

Synthesis Method ◽

Xrd Analysis ◽

Dip Coating ◽

Yttrium Iron ◽

Iron Garnet ◽

Dip Coating Technique ◽

Sol Gel Synthesis

In this study, an aqueous sol-gel synthesis method and subsequent dip-coating technique were applied for the preparation of yttrium iron garnet (YIG), yttrium iron perovskite (YIP), and terbium iron perovskite (TIP) bulk and thin films. The monophasic highly crystalline different iron ferrite powders have been synthesized using this simple aqueous sol-gel process displaying the suitability of the method. In the next step, the same sol-gel solution was used for the fabrication of coatings on monocrystalline silicon (100) using a dip-coating procedure. This resulted, likely due to substrate surface influence, in all coatings having mixed phases of both garnet and perovskite. Thermogravimetric (TG) analysis of the precursor gels was carried out. All the samples were investigated by X-ray powder diffraction (XRD) analysis. The coatings were also investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Mössbauer spectroscopy. Magnetic measurements were also carried out.

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Sol-gel synthesis and characterization of Ag nanoparticles in ZrO2 thin films

Journal of Materials Research ◽

10.1557/jmr.2009.0314 ◽

2009 ◽

Vol 24 (8) ◽

pp. 2541-2546 ◽

Cited By ~ 7

Author(s):

Eisuke Yokoyama ◽

Hironobu Sakata ◽

Moriaki Wakaki

Keyword(s):

Thin Films ◽

Sol Gel ◽

Composite Films ◽

Dip Coating ◽

Molar Ratio ◽

X Ray Diffraction ◽

Silver Surface ◽

Molar Ratios ◽

Sol Gel Synthesis

ZrO2 thin films containing silver nanoparticles were prepared using the sol-gel method with Ag to Zr molar ratios [Ag]/[Zr] = 0.11, 0.25, 0.43, 0.67, 1.00, 1.50, and 2.33. After dip coating on glass substrate, coated films were annealed at 200 and 300 °C in air. X-ray diffraction peaks corresponding to crystalline Ag were observed, but a specific peak corresponding to ZrO2 was not observed. At the molar ratio [Ag]/[Zr] = 0.25, the particle size of Ag distributed broadly centered at 17 nm for an annealing temperature of 200 °C and at 25 nm for 300 °C. The films annealed in air at 200 °C showed an absorption band centered at 450 nm because of the silver surface plasmon resonance, whereas films heated at 300 °C in air caused a red shift of the absorption to 500 nm. The absorption peak was analyzed using the effective dielectric function of Ag-ZrO2 composite films modeled with the Maxwell-Garnett expression.

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A Molecular Route to Dip-coated Transition Metal Nitride Thin Films.

MRS Proceedings ◽

10.1557/proc-848-ff2.2 ◽

2004 ◽

Vol 848 ◽

Author(s):

Andrew W. Jackson ◽

Andrew L. Hector

Keyword(s):

Thin Films ◽

Transition Metal ◽

Spin Coating ◽

Sol Gel ◽

Particle Growth ◽

Dip Coating ◽

Stable Emulsion ◽

Transition Metal Nitride ◽

Sol Gel Synthesis ◽

Gel Processing

ABSTRACTThere is an increasing interest in sol-gel synthesis of nitrides. The ability to deposit films of these materials by dip- or spin-coating will increase the range of applications in which they are viable and is an important step toward general sol-gel processing of nitride materials.With transition metals, the ammono based analogue of the well established alkoxy route to gels is inherently difficult to control. Due to the basicity of the system, the overwhelming tendency is of the starting materials to favour particle growth which results in a precipitate rather than a stable emulsion, unless both environment and synthetic pathway are carefully controlled. Hence reports to date of sol-gel routes to nitrides describe production of powders. We report work on a sol-gel route to titanium nitride with the ammonolysis of titanium amides controlled by temperature and chemical moderators, resulting in stable emulsions useful for dip-coating.

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Sol-Gel Derived Two-Dimensional Nanostructures of Calcium Phosphates

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.91.13 ◽

2014 ◽

Vol 91 ◽

pp. 13-18 ◽

Cited By ~ 4

Author(s):

A. Prichodko ◽

V. Jonauske ◽

M. Cepenko ◽

A. Beganskiene ◽

A. Kareiva

Keyword(s):

Thin Films ◽

Calcium Phosphates ◽

Steel Substrate ◽

Sol Gel ◽

Calcium Hydroxyapatite ◽

Xrd Analysis ◽

Dip Coating ◽

Force Microscopy ◽

Angle Measurements ◽

Main Components

Calcium hydroxyapatite (Ca10(PO4)6(OH)2, CHAp), tricalcium phosphate (Ca3(PO4)2, TCP) and calcium oxide (CaO) are the main components of inorganic part of human bones. Such synthetic nanocomposites could be very important implantable materials and using as substitute material for human hard tissues (bones and teeth). In this study, an aqueous sol-gel chemistry route has been developed to prepare nanostructured CHAp thin films on stainless steel substrate. For the preparation of thin films dip-coating and spin-coating techniques were used. The final samples were obtained by calcination of coatings for different time at 1000 °C. For the characterization of surface properties, the X-ray powder diffraction (XRD) analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM) and the contact angle measurements were recorded.

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Undoped and Eu3+ Doped Magnesium-Aluminium Layered Double Hydroxides: Peculiarities of Intercalation of Organic Anions and Investigation of Luminescence Properties

Materials ◽

10.3390/ma12050736 ◽

2019 ◽

Vol 12 (5) ◽

pp. 736 ◽

Cited By ~ 3

Author(s):

Aurelija Smalenskaite ◽

Lina Pavasaryte ◽

Thomas Yang ◽

Aivaras Kareiva

Keyword(s):

Layered Double Hydroxides ◽

Organic Anion ◽

Sol Gel ◽

Xrd Analysis ◽

X Ray Diffraction ◽

X Ray ◽

Organic Guests ◽

Double Hydroxides ◽

Scanning Electron

The Mg3/Al and Mg3/Al0.99Eu0.01 layered double hydroxides (LDHs) were fabricated using a sol-gel chemistry approach and intercalated with different anions through ion exchange procedure. The influence of the origin of organic anion (oxalate, laurate, malonate, succinate, tartrate, benzoate, 1,3,5-benzentricarboxylate (BTC), 4-methylbenzoate (MB), 4-dimethylaminobenzoate (DMB) and 4-biphenylacetonate (BPhAc)) on the evolution of the chemical composition of the inorganic-organic LDHs system has been investigated. The obtained results indicated that the type and arrangement of organic guests between layers of the LDHs influence Eu3+ luminescence in the synthesized different hybrid inorganic–organic matrixes. For the characterization of synthesis products X-ray diffraction (XRD) analysis, infrared (FTIR) spectroscopy, fluorescence spectroscopy (FLS), and scanning electron microscopy (SEM), were used.

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Sol–gel synthesis of calcium hydroxyapatite thin films on quartz substrate using dip-coating and spin-coating techniques

Journal of Sol-Gel Science and Technology ◽

10.1007/s10971-014-3394-5 ◽

2014 ◽

Vol 71 (3) ◽

pp. 437-446 ◽

Cited By ~ 12

Author(s):

Milda Malakauskaite-Petruleviciene ◽

Zivile Stankeviciute ◽

Aldona Beganskiene ◽

Aivaras Kareiva

Keyword(s):

Thin Films ◽

Spin Coating ◽

Quartz Substrate ◽

Sol Gel ◽

Calcium Hydroxyapatite ◽

Dip Coating ◽

Sol Gel Synthesis

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Thermal Annealing-Activated Crystallinity Metastasis of Al:ZnO Thin Films

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1109.181 ◽

2015 ◽

Vol 1109 ◽

pp. 181-185 ◽

Cited By ~ 1

Author(s):

Mohd Firdaus Malek ◽

Mohamad Hafiz Mamat ◽

M.Z. Musa ◽

M. Rusop

Keyword(s):

Thin Films ◽

Thermal Annealing ◽

Annealing Temperature ◽

Sol Gel ◽

Xrd Analysis ◽

Dip Coating ◽

X Ray Diffraction ◽

X Ray ◽

Dip Coating Technique ◽

Multilayered Thin Films

Multilayered thin films of aluminum-doped ZnO (Al:ZnO) have been deposited by the sol-gel dip coating technique. Experimental results indicated that the thermal annealing temperature affected the crystallinity of the Al:ZnO films. X-ray diffraction (XRD) analysis showed that thin films were preferentially orientated along the c-axis plane. The preferred orientation along (0 0 2) plane becomes more pronounced as the thermal annealing being increased. The film thickness ranges between 180 and 690 nm. In our experiments, the most optimum condition of Al:ZnO annealing temperature was both 500 oC.

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Sol-gel synthesis and characterization of hybrid inorganic-organic Tb(III)-terephthalate containing layered double hydroxides

Optical Materials ◽

10.1016/j.optmat.2018.04.048 ◽

2018 ◽

Vol 80 ◽

pp. 186-196 ◽

Cited By ~ 10

Author(s):

A. Smalenskaite ◽

A.N. Salak ◽

M.G.S. Ferreira ◽

R. Skaudzius ◽

A. Kareiva

Keyword(s):

Layered Double Hydroxides ◽

Sol Gel ◽

Synthesis And Characterization ◽

Sol Gel Synthesis ◽

Double Hydroxides

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On the Reconstruction Peculiarities of Sol–Gel Derived Mg2−xMx/Al1 (M = Ca, Sr, Ba) Layered Double Hydroxides

Crystals ◽

10.3390/cryst10060470 ◽

2020 ◽

Vol 10 (6) ◽

pp. 470 ◽

Cited By ~ 3

Author(s):

Ligita Valeikiene ◽

Marina Roshchina ◽

Inga Grigoraviciute-Puroniene ◽

Vladimir Prozorovich ◽

Aleksej Zarkov ◽

...

Keyword(s):

Layered Double Hydroxides ◽

Pore Diameter ◽

Sol Gel ◽

Earth Metal ◽

Nitrogen Adsorption ◽

Xrd Analysis ◽

X Ray ◽

Double Hydroxides ◽

Synthesized Materials ◽

First Time

In this study, the reconstruction peculiarities of sol–gel derived Mg2−xMx/Al1 (M = Ca, Sr, Ba) layered double hydroxides were investigated. The mixed metal oxides (MMO) were synthesized by two different routes. Firstly, the MMO were obtained directly by heating Mg(M)–Al–O precursor gels at 650 °C, 800 °C, and 950 °C. These MMO were reconstructed to the Mg2−xMx/Al1 (M = Ca, Sr, Ba) layered double hydroxides (LDHs) in water at 50 °C for 6 h (pH 10). Secondly, in this study, the MMO were also obtained by heating reconstructed LDHs at the same temperatures. The synthesized materials were characterized using X-ray powder diffraction (XRD) analysis and scanning electron microscopy (SEM). Nitrogen adsorption by the Brunauer, Emmett, and Teller (BET) and Barrett, Joyner, and Halenda (BJH) methods were used to determine the surface area and pore diameter of differently synthesized alkaline earth metal substituted MMO compounds. It was demonstrated for the first time that the microstructure of reconstructed MMO from sol–gel derived LDHs showed a “memory effect”.

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