EFFECT OF ANNEALING TEMPERATURE ON STRUCTURAL AND OPTICAL PARAMETERS OF SOL–GEL ROUTED MOLYBDENUM OXIDE THIN FILM

2015 ◽  
Vol 22 (04) ◽  
pp. 1550054 ◽  
Author(s):  
P. ADAL ARASU ◽  
R. VICTOR WILLIAMS

The influence of annealing temperature on structural and optical properties of sol–gel routed spin-coated molybdenum tri oxide ( MoO 3) thin films are studied. The higher annealing temperatures improve the crystalline nature of the film. The X-ray diffraction (XRD) study reveals the formation of α-orthorhombic phase at higher annealing temperature and amorphous nature at lower annealing temperature. The optical bandgap of molybdenum tri oxide ( MoO 3) film is found to be 3.3–3.8 eV, and the refractive index of the film is found to be 2.2–2.9. The dispersion curve of the refractive index shows that an abnormal dispersion in the absorption region and normal dispersion in the transparent region are observed. The optical polarizability, optical conductivity, dielectric constant, volume and surface energy loss parameters are evaluated.

2013 ◽  
Vol 334-335 ◽  
pp. 290-293 ◽  
Author(s):  
N. Baydogan ◽  
T. Ozdurmusoglu ◽  
Huseyin Cimenoglu ◽  
A.B. Tugrul

Doped ZnO:Al thin films were deposited on glass substrates by the solgel dip technique. Optical parameters such as the refractive index and the extinction coefficient tend to change with increasing annealing temperature.


Author(s):  
T. Pikula ◽  
T. Szumiata ◽  
K. Siedliska ◽  
V. I. Mitsiuk ◽  
R. Panek ◽  
...  

AbstractIn this work, BiFeO3 powders were synthesized by a sol–gel method. The influence of annealing temperature on the structure and magnetic properties of the samples has been discussed. X-ray diffraction studies showed that the purest phase was formed in the temperature range of 400 °C to 550 °C and the samples annealed at a temperature below 550 °C were of nanocrystalline character. Mössbauer spectroscopy and magnetization measurements were used as complementary methods to investigate the magnetic state of the samples. In particular, the appearance of weak ferromagnetic properties, significant growth of magnetization, and spin-glass-like behavior were observed along with the drop of average grain size. Mössbauer spectra were fitted by the model assuming cycloidal modulation of spins arrangement and properties of the spin cycloid were determined and analyzed. Most importantly, it was proved that the spin cycloid does not disappear even in the case of the samples with a particle size well below the cycloid modulation period λ = 62 nm. Furthermore, the cycloid becomes more anharmonic as the grain size decreases. The possible origination of weak ferromagnetism of the nanocrystalline samples has also been discussed.


2017 ◽  
Vol 31 (02) ◽  
pp. 1750006 ◽  
Author(s):  
Mohammad Hossein Ghorbani ◽  
Abdol Mahmood Davarpanah

Manganese oxides are of more interest to researchers because of their ability as catalysts and lithium batteries. In this research, MnO2nanowires with diameter about 45 nm were synthesized by sol–gel method at room temperature (RT). Effect of increasing the annealing temperature from 400[Formula: see text]C to 600[Formula: see text]C on crystalline structure of nanostructure were studied and average crystallite size was estimated about 22 nm. X-ray Diffraction (XRD) method, Energy-Dispersive X-ray Diffraction (EDXD), Scanning Electron Microscopy (SEM) and Vibrating Sample Magnetometer (VSM) were used to characterize the nanowires of MnO2.


2021 ◽  
pp. 2150081
Author(s):  
ERMAN ERDOGAN

In this study, spin coating, which is a chemical film layer thin film deposition method, was used for coronene films that were grown on Si substrates annealed at 325, 350 and 375[Formula: see text]K to examine the impacts on the optical properties of films. This method allows for easy control of the deposition parameters such as concentration, temperature and time as well as enables the film growth at low cost. Optical (UV–Vis) spectral measurements in the wavelength range from 200[Formula: see text]nm to 800[Formula: see text]nm were used to extract the bandgap information and to calculate various optical parameters of the spin-coated coronene films. The electronic transitions on the absorption of photons of suitable energy are of indirect allowed type. The corresponding optical bandgap ([Formula: see text]) was determined. Complex dielectric constants, dissipation factor, optical and electrical conductances and refractive index of coronene films were analyzed as a function of temperature. As the film annealing temperature was increased, the dielectric constants and the refractive index values increased, whereas the optical bandgap and electrical and optical conductivity values decreased.


2014 ◽  
Vol 21 (02) ◽  
pp. 1450027 ◽  
Author(s):  
YAQIANG LIU ◽  
XUELIAN DU ◽  
XUEQIN LIU

The vanadium pentoxide ( V 2 O 5) films were obtained by using sol–gel procedure and then were annealed at different temperature in air. The effect of different annealing temperatures on the composition, the microstructure, the surface morphology and the optical properties of the films were characterized by methods such as by X-ray diffraction, Raman spectroscopy, scanning electron microscopy and spectral transmittance. The results revealed that the film annealed at 150°C has amorphous structure and dense with a smooth surface and the films annealed at 300°C and 450°C have a polycrystalline V 2 O 5 structure with preferred growth orientation along (001) planes, the c-axis and perpendicular to the silicon substrate surface. From the spectral transmittance we determined the absorption edge using the Tauc plot. The results indicated that optical bandgap of V 2 O 5 thin films decreased with annealing temperature.


2020 ◽  
Vol 981 ◽  
pp. 51-58
Author(s):  
Agus Geter Edy Sutjipto ◽  
Yit Pei Shian ◽  
Ali Shaitir ◽  
Mohamad Ashry Jusoh ◽  
Ari Legowo

This research deals with ambient energy harvesting by using zinc oxide thin film. The objectives of this thesis are to prove the ZnO film as a piezoelectric material can produce electric when vibration is applied and determine its optimal voltage. The thesis describes the sol gel spin coating technique to fabricate zinc oxide thin film. Zinc acetate dehydrate, absolute ethanol and diethanolamine were used in this thesis to act as sol gel precursor. Sol gel was coated on glass slide which wrapped by aluminum foil. The thin film was formed after preheating and annealing. The thin film was characterized by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopy (FESEM), Photoluminescence spectroscopy (PL) and Ultraviolet-visible spectroscopy (UV-Vis) as well as analyzed using vibration technique. From XRD results, the films were preferentially diffracted at around 65° which corresponding to (1 1 2) diffraction phase. From FESEM results, it was observed that when the spin speed was increased at same annealing temperature, the thickness was also decreased. When the annealing temperature was increased at same spin speed, both grain size and thickness were increased. From the PL results, there was only film with spin speed of 2000 rpm and annealing temperature of 300 °C had slightly left wavelength which was 380 nm. Annealing temperature would affect only the intensity of PL wavelength. From the results of UV-Vis, it was observed that when the spin speed was increased at same annealing temperature, the band gap was decreased. When the annealing temperature was increased at same spin speed, the band gap was decreased. Piezoelectric test had proven the ZnO film could produce electricity. The maximum voltage (20.7 mV) was produced by the ZnO film with spin speed of 2000 rpm and annealing temperature of 300 °C.


2012 ◽  
Vol 151 ◽  
pp. 314-318
Author(s):  
Ching Fang Tseng ◽  
Cheng Hsing Hsu ◽  
Chun Hung Lai

This paper describes microstructure characteristics of MgAl2O4 thin films were deposited by sol-gel method with various preheating temperatures and annealing temperatures. Particular attention will be paid to the effects of a thermal treatment in air ambient on the physical properties. The annealed films were characterized using X-ray diffraction. The surface morphologies of treatment film were examined by scanning electron microscopy and atomic force microscopy. At a preheating temperature of 300oC and an annealing temperature of 700oC, the MgAl2O4 films with 9 μm thickness possess a dielectric constant of 9 at 1 kHz and a dissipation factor of 0.18 at 1 kHz.


2015 ◽  
Vol 1088 ◽  
pp. 81-85 ◽  
Author(s):  
T.N. Myasoedova ◽  
Victor V. Petrov ◽  
Nina K. Plugotarenko ◽  
Dmitriy V. Sergeenko ◽  
Galina Yalovega ◽  
...  

Thin SiO2ZrO2films were prepared, up to 0.2 μm thick, by means of the sol–gel technology and characterized by a Scanning electron microscopy and X-ray diffraction. It is shown the presence of monoclinic, cubic and tetragonal phases of ZrO2in the SiO2matrix. The crystallites sizes depend on the annealing temperature of the film and amount to 35 and 56 nm for the films annealed at 773 and 973 K, respectively. The films resistance is rather sensitive to the presence of NO2and O3impurity in air at lower operating temperatures in the range of 30-60°C.


2013 ◽  
Vol 27 (27) ◽  
pp. 1350153 ◽  
Author(s):  
ALI BAHARI ◽  
REZA GHOLIPUR ◽  
MARYAM DERAKHSHI

Styrene-doped ZrLaO y nanostructures were obtained by sol–gel method low-temperature synthesis. The nanostructures were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), atomic force microscope (AFM) and transmission electron microscopy (TEM) techniques. The observation using SEM and TEM revealed that the ring-shaped nanostructures were very uniform. Further characterization using XRD disclosed that the cohesion of the samples was controllable with annealing temperatures in the range of 800–1500°C. Cohesion property was investigated for the samples. The cohesion increased when increasing the annealing temperature. This was linked to the reinforcement of the oxygen bound on the ZrLaO y nanostructures The shape of nanostructures showed a transformation from a ring-shaped growth mode to a hole-surfaced growth mode with increasing annealing temperature. The styrene-doped ZrLaO y nanostructures with controllable crystallinity will have great potential for various applications in fuel, cells, batteries, electronics devices and chemical sensors.


Sign in / Sign up

Export Citation Format

Share Document