Structure and Optical Properties of TiO2 Thin Films Prepared by a Sol-Gel Processing

AbstractTitanium dioxide (TiO2) thin films were deposited on CR-39 by a sol-gel dip coating route with different withdrawal speeds ranging from 250 to 350 mm/s. The TiO2 thin films were characterised by x-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy, ellipsometry, and ultraviolet (UV)-visible (VIS)-near infrared (NIR) spectro-photometry. The role of withdrawal speed on the thickness of thin films to tailor properties of TiO2 thin films was studied. The XRD results revealed that all the films are amorphous in nature. TiO2 thin films deposited at different withdrawal speeds exhibit a decrease in transmission with an increase in speed. The direct optical band gap of the films has been estimated to be in the range 3.48–3.00 eV by UV-VIS-NIR spectro-photometry and 3.52–3.38 eV by ellipsometry. TiO2 is a potential prospect in microelectronic applications and can serve as an absorber layer for photovoltaic devices. Surface morphology is granular with an increase in grain size and an increase in withdrawal speed.

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Resistive Switching Behaviour of Dip Coated ZnO Films with the Changing with Drawal Speed

Materials Science Forum ◽

10.4028/www.scientific.net/msf.978.384 ◽

2020 ◽

Vol 978 ◽

pp. 384-389

Author(s):

Sritama Roy ◽

Saswati Soumya Dash ◽

Prasanna Kumar Sahu ◽

Smita Mishra ◽

Jyoti Prakash Kar

Keyword(s):

Thin Films ◽

Resistive Switching ◽

Sol Gel ◽

Dip Coating ◽

Zno Films ◽

X Ray Diffraction ◽

Thin Film Thickness ◽

Withdrawal Speed ◽

Current Voltage ◽

P Type

Zinc Oxide (ZnO) thin films were produced by the sol gel dip coating process on the p-type silicon substrate with various withdrawal speeds changing from 1 to 4 cm/min, respectively. The films were annealed at a temperature of 500 °C for an hour in air ambient. The thin film thickness was found to be raised with the rise in withdrawal speed. The uniform distribution of the grains was appeared for all the films. The evolution of c-axis oriented (002) peak was revealed from X-ray diffraction (XRD) studies. The microstructural and optical properties of ZnO films were investigated by Raman, FTIR and photoluminescence spectroscopy (PL). The resistive switching properties of ZnO based memristors were studied by performing the current-voltage (I-V) measurements, where the thin films coated with lower withdrawal speed, have shown better switching property with rapid rise and fall of current during SET and RESET process, respectively.

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Characteristics and optical properties of Fe3+ doped SiO2/TiO2 thin films prepared by the sol-gel dip-coating method

Science and Technology Development Journal ◽

10.32508/stdj.v16i1.1424 ◽

2013 ◽

Vol 16 (1) ◽

pp. 92-100

Author(s):

Chien Mau Dang ◽

Dam Duy Le ◽

Tam Thi Thanh Nguyen ◽

Dung Thi My Dang

Keyword(s):

Thin Films ◽

Optical Properties ◽

Sol Gel ◽

Dip Coating ◽

X Ray Diffraction ◽

Tio2 Thin Films ◽

Water Contact ◽

Glass Substrates ◽

Coating Method ◽

Dip Coating Method

In this study, we have successfully synthesized Fe3+ doped SiO2/TiO2 thin films on glass substrates using the sol-gel dip-coating method. After synthesizing, the samples were annealed at 5000C in the air for 1 hour. The characteristics and optical properties of Fe3+ doped SiO2/TiO2 films were then investigated by X-ray diffraction (XRD), ultraviolet-visible spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FT-IR). An antifogging ability of the glass substrates coated with the fabricated film is investigated and explained by a water contact angle under visible-light. The analyzed results also show that the crystalline phase of TiO2 thin films comprised only the anatase TiO2, but the crystalline size decreased from 8.8 to 5.9 nm. We also observed that the absorption edge of Fe3+- doped SiO2/TiO2 thin films shifted towards longer wavelengths (i.e. red shifted) from 371.7nm to 409.2 nm when the Fe3+-doped concentration increased from 0 to 1 % mol.

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Effect of Withdrawal Speed on the Structural, Optical and Morphological Properties of NiO Thin Films Obtained by Sol-Gel Dip Coating Method

International Journal of Engineering Research in Africa ◽

10.4028/www.scientific.net/jera.31.29 ◽

2017 ◽

Vol 31 ◽

pp. 29-35 ◽

Cited By ~ 2

Author(s):

Abdelouahab Noua ◽

Rebai Guemini ◽

Hichem Farh ◽

Mourad Zaabat

Keyword(s):

Thin Films ◽

Near Infrared ◽

Sol Gel ◽

Optical Transmittance ◽

Dip Coating ◽

Morphological Properties ◽

Speed Increase ◽

Withdrawal Speed ◽

Coating Method ◽

Dip Coating Method

In this study, pure nickel oxide thin films were prepared by a sol-gel dip coating method with different withdrawal speeds, onto glass substrates and their structural, optical and morphological properties were investigated. The structural properties of NiO films were characterized by X-ray diffraction (XRD), Polycrystalline structures of the prepared films were detected. The optical properties of the films were studied by UV–visible spectrophotometer and the optical transmittance of the films within the visible and near infrared region was found to be more than 75% and decrease when the withdrawal speed increase. The surface morphology of the films was observed by atomic force microscopy and it was found that the root mean square (RMS) roughness increases from 3.78 to 15 nm when the withdrawal speed increased from 30 to70 mm/min. Thus, the withdrawal speed is a key factor to change the NiO thin films properties.

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Synthesis and Characterization of Nanocrystalline TiO2 Thin Films by Sol-Gel Dip Coating Method

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.678.108 ◽

2013 ◽

Vol 678 ◽

pp. 108-112 ◽

Cited By ~ 2

Author(s):

Narayanaswamy Gokilamani ◽

N. Muthukumarasamy ◽

Mariyappan Thambidurai

Keyword(s):

Thin Films ◽

Sol Gel ◽

Dip Coating ◽

X Ray Diffraction ◽

Tio2 Thin Films ◽

Atomic Force ◽

Coating Method ◽

Nanocrystalline Titanium ◽

Dip Coating Method

Nanocrystalline titanium dioxide (TiO2) thin films have been prepared by dip coating method. The TiO2 thin films have been coated on glass substrate and annealed at 400, 450 and 500° C respectively. The X- ray diffraction pattern shows that TiO2 nanocrystalline thin films are of anatase structure and the grain size is found to be in the range of 20-35 nm. The annealed films have been observed to be nanocrystalline in nature and the crystallinity has been observed to improve on annealing. The surface topography of the films has been studied using atomic force microscope. The optical properties have been studied using transmittance spectra. The band gap has been found to lie in the range of 3.70 to 3.83 eV depending on the annealing temperature.

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BaTiO3 Thin Films Prepared By Dip-Coating Process

MRS Proceedings ◽

10.1557/proc-341-379 ◽

1994 ◽

Vol 341 ◽

Cited By ~ 3

Author(s):

Nelcy Della ◽

Santina Mohallem

Keyword(s):

Thin Films ◽

Sol Gel ◽

Dip Coating ◽

Molar Ratio ◽

X Ray Diffraction ◽

Titanium Alkoxides ◽

X Ray ◽

Withdrawal Speed ◽

Sol Gel Process ◽

Tetragonal Batio

AbstractThin films of pure barium titanate have been prepared by the sol-gel process from organomettalic sols containing titanium alkoxides and barium acetate (molar ratio [Ba]/[Ti]=l). It leads to transparent, homogeneous and adherent coatings. The influence of various parameters such as chemical concentration, viscosity, withdrawal speed and temperature of densification on film thickness is described. The films were characterized by X-ray diffraction during their heat treatment. Their crystallization temperature was observed to be around 450°C. No variations in the optical properties were observed during the crystallization, and it occurred without the appearance of cracks or pinholes. Tetragonal BaTiO3 structure was observed, and the ferroeletric properties were investigated as functions of thickness and grain size.

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The effect of the withdrawal speed on properties of nickel oxide thin films

Zeitschrift für Kristallographie - Crystalline Materials ◽

10.1515/zkri-2019-0028 ◽

2019 ◽

Vol 234 (10) ◽

pp. 647-655

Author(s):

Zohra Nazir Kayani ◽

Atiqa Aslam ◽

Rabia Ishaque ◽

Syeda Nosheen Zahra ◽

Hifza Hanif ◽

...

Keyword(s):

Thin Films ◽

Nickel Oxide ◽

Band Gap ◽

Sol Gel ◽

Average Crystallite Size ◽

Dip Coating ◽

Oxide Thin Films ◽

Withdrawal Speed ◽

Sem Micrograph ◽

Nickel Oxide Thin Films

Abstract Nickel oxide thin films have been prepared by sol-gel dip-coating technique on glass substrate. It is shown that nickel oxide thin films have poly crystalline nature. Nickel oxide thin films exhibit high transmission (39–85%) in the wavelength range of 400–900 nm, strong absorption between 300 and 400 nm wavelengths and decrease of band gap values are in the range 3.69–3.27 eV with increase of withdrawal speed. High band gap at low withdrawal speed is because of the small average crystallite size, which decreases with increase in withdrawal speed. The SEM micrograph shows cubic crystallites and surface of thin films become dense, smooth and homogeneous with an increase in withdrawal speed. Assessment of nickel oxide deposition conditions provides gateway for effective and cheap solar cells.

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Preparation and characterization of V2O5 doped SiO2-TiO2 thin films

Open Engineering ◽

10.2478/s13531-011-0041-6 ◽

2012 ◽

Vol 2 (1) ◽

Author(s):

Marek Nocuń ◽

Sławomir Kwaśny

Keyword(s):

Thin Films ◽

Band Gap ◽

Photoelectron Spectroscopy ◽

Sol Gel ◽

Dip Coating ◽

Band Gap Energy ◽

Tio2 Thin Films ◽

Glass Substrates ◽

Gel Technique

AbstractIn our investigation, V doped SiO2/TiO2 thin films were prepared on glass substrates by dip coating sol-gel technique. Chemical composition of the samples was studied by X-ray photoelectron spectroscopy (XPS). Transmittance of the samples was characterized using UV-VIS spectrophotometry. Subsequently band-gap energy (Eg) was estimated for these films. Powders obtained from sols were characterized by FTIR spectroscopy. It was found that vanadium decreases optical band gap of SSiO2/TiO2 films.

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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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