scholarly journals The structural studies of aluminosilicate gels and thin films synthesized by the sol-gel method using different Al2O3 and SiO2 precursors

2015 ◽  
Vol 33 (4) ◽  
pp. 732-741 ◽  
Author(s):  
Anna Adamczyk
Keyword(s):  
Thin Films ◽  
Sol Gel ◽  
Porous Ceramics ◽  
Dip Coating ◽  
Treatment Temperature ◽  
Gel Method ◽  
Sol Gel Method ◽  
Coating Method ◽  
Different Temperatures ◽  
Ft Ir

AbstractAluminosilicate materials were obtained by sol-gel method, using different Al2O3 and SiO2 precursors in order to prepare sols based on water and organic solvents. As SiO2 precursors, Aerosil 200TM and tetraethoxysilane TEOS: Si(OC2H5)4 were applied, while DisperalTM and aluminium secondary butoxide ATSB: Al(OC4H9)3 were used for Al2O3 ones. Bulk samples were obtained by heating gels at 500 °C, 850 °C and at 1150 °C in air, while thin films were synthesized on carbon, steel and alundum (representing porous ceramics) substrates by the dip coating method. Thin films were annealed in air (steel and alundum) and in argon (carbon) at different temperatures, depending on the substrate type. The samples were synthesized as gels and coatings of the composition corresponding the that of 3Al2O3·2SiO2 mullite because of the specific valuable properties of this material. The structure of the annealed bulk samples and coatings was studied by FT-IR spectroscopy and XRD method (in standard and GID configurations). Additionally, the electron microscopy (SEM) together with EDS microanalysis were applied to describe the morphology and the chemical composition of thin films. The analysis of FT-IR spectra and X-ray diffraction patterns of bulk samples revealed the presence of γ-Al2O3 and δ-Al2O3 phases, together with the small amount of SiO2 in the particulate samples. This observation was confirmed by the bands due to vibrations of Al–O bonds occurring in γ-Al2O3 and δ-Al2O3 structures, in the range of 400 to 900 cm−1. The same phases (γ-Al2O3 and δ-Al2O) were observed in the deposited coatings, but the presence of particulate ones strongly depended on the type of Al2O3 and SiO2 precursor and on the heat treatment temperature. All thin films contained considerable amounts of amorphous phase.

Preparation of La0.75Sr0.25Cr0.5Mn0.5O3-δ Nanometer Powders by Sol-Gel Method and Research about its Electrochemical Performance

2013 ◽  
Vol 712-715 ◽  
pp. 257-261
Author(s):  
Yin Lin Wu ◽  
Qing Hui Wang ◽  
Ling Wang ◽  
Hai Yan Zhao
Keyword(s):  
Heat Treatment ◽  
Particle Size ◽  
Electrochemical Performance ◽  
Heat Treatment Temperature ◽  
Sol Gel ◽  
Treatment Temperature ◽  
Preparation Process ◽  
Gel Method ◽  
Sol Gel Method ◽  
Ft Ir

The La0.75Sr0.25Cr0.5Mn0.5O3-δnanometer powders were prepared by citric acid sol-gel method.The samples were characterized by DTA, FT-IR, XRD, TEM techniques. The preparation process, morphology of synthesized powders, the best heat-treatment temperature and the electrochemical performance had been studied. The results show that the spherical nanometer powders can be obtained and the best heat-treatment temperature is 800°C. The particle size is about 30nm and Ea is 0.071 eV.

Studying on Preparation of AZO Thin Films with Sol-Gel Method

2010 ◽  
Vol 152-153 ◽  
pp. 868-873 ◽  
Author(s):  
Xiu Ling Lv ◽  
Yu Bo Dou ◽  
Juan Wang ◽  
Ying Xu
Keyword(s):  
Thin Films ◽  
Optical Properties ◽  
Sol Gel ◽  
Treatment Temperature ◽  
Zno Films ◽  
Gel Method ◽  
Sol Gel Method ◽  
Crystallization Properties ◽  
Doped Zno ◽  
Micro Morphology

Al doped ZnO thin films（AZO films） was prepared by sol-gel method. The influence of Parameters of different processes on the crystallization properties, micro-morphology and optical properties of this kind of films were studied, using by X-ray diffractometer, filed emission stereoscan, spectral photometer, hall admeasuring apparatus. The results indicated that the crystallization properties, micro-morphology and optical properties of Al doped ZnO films were best on the condition that the sol density was 0.5mol/L, hat treatment temperature is 600 and there is a 8-layer coating.

Structure of Hydrogen Gas Sensing TiO2 Thin Films Prepared by Sol-Gel Method and their Comparison with Magnetron Sputtered Films

2013 ◽  
Vol 543 ◽  
pp. 293-296 ◽  
Author(s):  
G. Plesch ◽  
A.A. Haidry ◽  
M. Gregor ◽  
P. Durina ◽  
J. Gregus ◽  
...  
Keyword(s):  
Thin Films ◽  
Magnetron Sputtering ◽  
Gas Sensing ◽  
Sol Gel ◽  
Rutile Phase ◽  
Hydrogen Gas ◽  
Gel Method ◽  
Sensing Properties ◽  
Sol Gel Method ◽  
Coating Method

TiO2thin films with a thickness of about 150 nm were deposited by spin coating method on sapphire substrate from a sol-gel system. The hydrogen sensing properties of TiO2films annealed at various temperatures were studied and correlated with their structure, optical and electrical properties. The annealing temperatures in the range of 600 800 °C lead to anatase films with a roughness in the range of 0.6 0.9 nm. Their sensitivity towards hydrogen is low. The thin films annealed at temperatures in the range 900 1000 °C consist of rutile phase and their roughness increased to 11.7 13.5 nm. They showed good hydrogen sensitivity with optimal operating temperature 200 250 °C. The structure and sensing properties of the prepared films are compared with those synthesized with magnetron sputtering. The maximum of sensitivity was measured on the thin films with diameter of the grains about 100 nm in both cases, i.e. on thin films prepared by sol-gel method as well as on thin films prepared by magnetron sputtering. The maximum sensitivity correlates with the diameter of the grains and dont depend on the allotropy of the titanium dioxide anatase or rutile.

Preparation of Nanocrystalline Titanium Dioxide (TiO2) Thin Films by the Sol-Gel Dip Coating Method

2012 ◽  
Vol 16 ◽  
pp. 105-111 ◽  
Author(s):  
Raouf Mechiakh ◽  
R. Gheriani ◽  
R. Chtourou
Keyword(s):  
Thin Films ◽  
Titanium Dioxide ◽  
Sol Gel ◽  
Dip Coating ◽  
Treatment Temperature ◽  
Coating Method ◽  
Type Semiconductor ◽  
Nanocrystalline Titanium ◽  
Dip Coating Method ◽  
Titanium Dioxide Thin Films

Titanium dioxide thin films have been prepared by the sol–gel dip-coating method on an ITO substrate. The samples obtained were characterized by different experimental techniques: XRD, Raman, FTIR, spectroscopy of the electrochemical potential and SEM. The X-ray diffraction results showed that the TiO2 thin film obtained for a layer, after a temperature of annealing (400°C) and at the speeds of steeping between 2 and 10 cm∙s-1 was amorphous, and transformed into anatase–brookite at 0.6 cm∙s-1 for 400°C. The data of Raman spectroscopy is in good agreement with the DRX results. Observation by scanning electron microscope shows that the coating was transparent and homogeneous without any visual cracking over a wide area, and the increase in the treatment temperature did not affect the uniformity of the film. The interface of our layers to behaved like a n-type semiconductor.

scholarly journals Antimicrobial Activity of Thin Solid Films of Silver Doped Hydroxyapatite Prepared by Sol-Gel Method

2014 ◽  
Vol 2014 ◽  
pp. 1-8 ◽  
Author(s):  
Simona Liliana Iconaru ◽  
Patrick Chapon ◽  
Philippe Le Coustumer ◽  
Daniela Predoi
Keyword(s):  
Thin Films ◽  
Antimicrobial Activity ◽  
Sol Gel ◽  
Optical Emission ◽  
Antimicrobial Effect ◽  
Gel Method ◽  
Sol Gel Method ◽  
E Coli ◽  
Ft Ir

In this work, the preparation and characterization of silver doped hydroxyapatite thin films were reported and their antimicrobial activity was characterized. Silver doped hydroxyapatite (Ag:HAp) thin films coatings substrate was prepared on commercially pure Si disks by sol-gel method. The silver doped hydroxyapatite thin films were characterized by various techniques such as Scanning electron microscopy (SEM) with energy Dispersive X-ray attachment (X-EDS), Fourier transform infrared spectroscopy (FT-IR), and glow discharge optical emission spectroscopy (GDOES). These techniques have permitted the structural and chemical characterisation of the silver doped hydroxyapatite thin films. The antimicrobial effect of the Ag:HAp thin films onEscherichia coliandStaphylococcus aureusbacteria was then investigated. This is the first study on the antimicrobial effect of Ag:HAp thin films obtained by sol-gel method. The results of this study have shown that the Ag:HAp thin films withxAg=0.5are effective againstE. coliandS. aureusafter 24 h.

Preparation of Ti/Cu Oxide Coating on Alumina by Sol-Gel Method

2009 ◽  
Vol 620-622 ◽  
pp. 457-460
Author(s):  
Ke Zheng Sang ◽  
Lin Liu ◽  
De Jun Zeng ◽  
Zhang Zeng Fan
Keyword(s):  
Infrared Spectroscopy ◽  
Glass Substrate ◽  
Sol Gel ◽  
Oxide Coating ◽  
Dip Coating ◽  
Anatase Tio2 ◽  
Gel Method ◽  
Sol Gel Method ◽  
Coating Method ◽  
Dip Coating Method

Using TiCl4 and CuCl2 as precursors, the sols were prepared. The coatings of Ti/Cu oxide were formed on both glass and alumina substrates by dip-coating method. XRD results showed that the coatings could be composed of anatase TiO2, CuO and M6O type oxides. The M6O type oxide on glass substrate is in the form of Cu3Ti3O, however is Cu2Ti4O on alumina substrate. The formations of the CuO and M6O are related to the Cu:Ti ratio. A high Cu:Ti ratio corresponds to the CuO, whereas to the M6O. Also the sols were analyzed by infrared spectroscopy and the mechanism of the formation of the coatings was discussed in the paper.

Synthesis of Sm–Co nanoparticles by sol–gel method

2018 ◽  
Vol 32 (34n36) ◽  
pp. 1840069 ◽  
Author(s):  
Wei Wu ◽  
Jinshan Zhang ◽  
Pengjun Cao ◽  
Jiling Dong ◽  
Hao Ding
Keyword(s):  
Sol Gel ◽  
Reduction Process ◽  
Treatment Temperature ◽  
Complexing Agents ◽  
Microstructural Investigation ◽  
Gel Method ◽  
Sol Gel Method ◽  
Ft Ir ◽  
Co Nanoparticles ◽  
Reductive Annealing

Sm–Co nanoparticles have promising applications in both scientific and industrial fields. In this paper, Sm–Co single-crystal nanoparticles were prepared using respective metal salts and complexing agents, such as citric acid by Pechini-type sol–gel method. The mixture solution was heated to form a highly viscous gel, and then heated at different temperatures to achieve SmCo-oxide. And then Sm–Co particles were yielded by reductive annealing of the precursors. Phase analysis, microstructural investigation and magnetic properties were performed by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), Fourier transform infrared (FT-IR) and VSM. TGA trace analysis of the gel determined the heat treatment temperature. XRD results showed that SmCoO3 and Co3O4 were obtained at 800[Formula: see text]C, FT-IR spectrometry analysis also verified the results. In the calcium-thermal reduction process, Sm2O3 and Co were obtained after reductive annealing at 800[Formula: see text]C, meanwhile Sm–Co nanoparticles were formed at 850[Formula: see text]C. FESEM analysis revealed that the Sm–Co nanoparticles were composed in the form of spherical granules and exhibited well distribution with size in the range of 100 nm. The room temperature saturation magnetization and coercivity of the Sm–Co nanoparticles were 49.61 emu/g and 3.53 kOe, respectively.

An enhancement in structural and superconducting properties of Bi2212 epitaxial thin films grown by the Pechini sol–gel method

2013 ◽  
Vol 46 (2) ◽  
pp. 379-386 ◽  
Author(s):  
Xiaoming Lu ◽  
Tianlin Wang ◽  
Yaming Zhang ◽  
M. Babar Shahzad ◽  
Yang Qi
Keyword(s):  
Thin Films ◽  
Transition Temperature ◽  
Sol Gel ◽  
Superconducting Thin Films ◽  
Epitaxial Thin Films ◽  
Superconducting Properties ◽  
Gel Method ◽  
Sol Gel Method ◽  
Sintering Time ◽  
Coating Method

Bi2Sr2CaCu2O8+δ(Bi2212) superconducting thin films were prepared by the Pechini sol–gel method using nitrates as reactants. The precursor sol was deposited on SrTiO3(001) single-crystal substratesviathe spin-coating method, and the results revealed the lowering of the Bi2212 phase-transition temperature; meanwhile the sintering time was significantly reduced. According to this investigation, the phase purity and crystallinity of Bi2212 thin films were obviously improved owing to the stable gel mechanism; theTc,onsettransition temperature value of the purec-axis Bi2212 thin films rose to about 95 K.

Sign in / Sign up

Export Citation Format

Share Document