09-02-2013, 02:53 PM
PREPARATION AND CHARACTERIZATION OF UNDOPED sno2 THIN FILMS PREPARED BY SPRAY PYROLYSIS TECHNIQUE
[attachment=50370]
THIN FILM DEPOSITION
The film deposition using the spray pyrolysis technique spraying a metal salt solution onto a heated substrate.
Droplets impact on the substrate surface, spread into a disk shaped structure, and undergo thermal decomposition.
The shape and size of the disk depends on the momentum and volume of the droplet, as well as the substrate temperature.
Consequently, the film is usually composed of overlapping disks of metal salt being converted to oxide on the heated substrate.
THIN FILM SPRAY PYROLYSIS
The chemical technique of Spray pyrolysis which is simile to handle economically viable is used for several decades in glass industries and in solar cell production to deposits electrically conducting electrodes.
Spray pyrolysis principle involved in the formation of metal oxide film is that when a droplet of sprayed metallic salt solution in the presents of oxygen atmosphere reaches the hot substrates, under goes pyrolytic decomposition and form a thin film.
USES OF STANNOUS OXIDE
The dominant use of stannous oxide is as a precursor in manufacturing of other, typically divalent, tin compounds or salts. Stannous oxide may also be employed as a reducing agent and in the creation of ruby glass. It has a minor use as an etherification catalyst.
Cerium (III) oxide in ceramic form, together with Tin(II) oxide (SnO) is used for illumination with UV light.
EXPERIMENTAL STUDIES
FOURIER TRANSFORM INFRARED SPECTROSCOPY
FTIR is a powerful tool for identifying types of chemical bonds in a molecule by producing an infrared absorption spectrum that is like a molecular “fingerprint”.
FTIR is most useful for identifying chemicals that are either organic or inorganic. It can be utilized to quantitative some components of an unknown mixture.
FTIR can be applied to the analysis of solids, liquids, and gasses.
Today’s FTIR instruments are computerized which makes them faster and more sensitive than the older dispersive instruments.
BAND GAP STUDIES
The optical energy band gap was calculated from the absorption values of the different samples. Band gap is the energy gap between the conduction band and the values band is of the order of electron volt eV. Here the estimation was done from the position of the absorption edge. In order to estimate the energy band gap values for the sample calculators were made from the recorded absorption values.
The absorption coefficient is calculated using the formula α=2.303*Abs./t and with the photon energy hν, the values of hνα and (hνα)2 were also found for the sample.
[attachment=50370]
THIN FILM DEPOSITION
The film deposition using the spray pyrolysis technique spraying a metal salt solution onto a heated substrate.
Droplets impact on the substrate surface, spread into a disk shaped structure, and undergo thermal decomposition.
The shape and size of the disk depends on the momentum and volume of the droplet, as well as the substrate temperature.
Consequently, the film is usually composed of overlapping disks of metal salt being converted to oxide on the heated substrate.
THIN FILM SPRAY PYROLYSIS
The chemical technique of Spray pyrolysis which is simile to handle economically viable is used for several decades in glass industries and in solar cell production to deposits electrically conducting electrodes.
Spray pyrolysis principle involved in the formation of metal oxide film is that when a droplet of sprayed metallic salt solution in the presents of oxygen atmosphere reaches the hot substrates, under goes pyrolytic decomposition and form a thin film.
USES OF STANNOUS OXIDE
The dominant use of stannous oxide is as a precursor in manufacturing of other, typically divalent, tin compounds or salts. Stannous oxide may also be employed as a reducing agent and in the creation of ruby glass. It has a minor use as an etherification catalyst.
Cerium (III) oxide in ceramic form, together with Tin(II) oxide (SnO) is used for illumination with UV light.
EXPERIMENTAL STUDIES
FOURIER TRANSFORM INFRARED SPECTROSCOPY
FTIR is a powerful tool for identifying types of chemical bonds in a molecule by producing an infrared absorption spectrum that is like a molecular “fingerprint”.
FTIR is most useful for identifying chemicals that are either organic or inorganic. It can be utilized to quantitative some components of an unknown mixture.
FTIR can be applied to the analysis of solids, liquids, and gasses.
Today’s FTIR instruments are computerized which makes them faster and more sensitive than the older dispersive instruments.
BAND GAP STUDIES
The optical energy band gap was calculated from the absorption values of the different samples. Band gap is the energy gap between the conduction band and the values band is of the order of electron volt eV. Here the estimation was done from the position of the absorption edge. In order to estimate the energy band gap values for the sample calculators were made from the recorded absorption values.
The absorption coefficient is calculated using the formula α=2.303*Abs./t and with the photon energy hν, the values of hνα and (hνα)2 were also found for the sample.