Nb2o5 Film Analysis
Abstract:
The optical and photocatalytic properties of Nb2O5 sculptured thin films (STF) are investigated. Films are synthesized via sol- gel route using spin coating technique. The sol is prepared from niobium ethoxide. The films are prepared at different rpm to tailor the thickness. The structures of the films are investigated through XRD measurements. Refractive index, extinction coefficient and thickness of the films are determined from Variable Angle Spectroscopic Ellipsometery. The absorbance and transmittance is recorded using UV-Vis spectrophotometer. The impact of post deposition calcinations at 500 °C on the structural, optical properties of the films & photocatalysis of Nb2O5 is also studied. The effects of thickness on refractive …show more content…
[4-7] Nb2O5 is a semiconductor like TiO2 with a large band gap (3.2eV) and conduction band at least 250mV above than TiO2. [8] Photoelectrochemical studies in the UV-spectral region have shown that Nb2O5 sol-gel films present a photoelectric effect but smaller than that of TiO2 films. [9] The sol- gel method involves spin-coating or dip-coating of the oxide sol on a substrate. Thin films with minimal thickness are generally desired because not only are they more economical to fabricate but also they can often lead to improved performance of the films. Catalytic oxidation of alcohols to carbonyl compound is widely used in industrial and organic chemistry. [10-12] Therefore, photoreactions in presence of catalyst have recently attracted noticeable attention. TiO2 has been one of the examples which is been used in vapor phase transformation of lower alcohols at high temperatures. [13-17] Tetsuya Shishido et.al reported an effective, solvent free photooxidation of higher alcohols using molecular oxygen over Nb2O5. [18] However, very few reports are present on photooxidation and to the best of our knowledge no report is present on the effect of thickness on the optical and photocatalytic activity of niobia thin films.
The present study involves the comparative evaluation of the effect of thickness on optical properties of Nb2O5 films and photooxidation of alcohols. The films were sculptured by spin coating at different rev. /min. to obtain thickness in desired range. The optical properties like refractive index, extinction coefficient, absorbance, transmittance and their dependence on thickness of films are also investigated and
The optical and photocatalytic properties of Nb2O5 sculptured thin films (STF) are investigated. Films are synthesized via sol- gel route using spin coating technique. The sol is prepared from niobium ethoxide. The films are prepared at different rpm to tailor the thickness. The structures of the films are investigated through XRD measurements. Refractive index, extinction coefficient and thickness of the films are determined from Variable Angle Spectroscopic Ellipsometery. The absorbance and transmittance is recorded using UV-Vis spectrophotometer. The impact of post deposition calcinations at 500 °C on the structural, optical properties of the films & photocatalysis of Nb2O5 is also studied. The effects of thickness on refractive …show more content…
[4-7] Nb2O5 is a semiconductor like TiO2 with a large band gap (3.2eV) and conduction band at least 250mV above than TiO2. [8] Photoelectrochemical studies in the UV-spectral region have shown that Nb2O5 sol-gel films present a photoelectric effect but smaller than that of TiO2 films. [9] The sol- gel method involves spin-coating or dip-coating of the oxide sol on a substrate. Thin films with minimal thickness are generally desired because not only are they more economical to fabricate but also they can often lead to improved performance of the films. Catalytic oxidation of alcohols to carbonyl compound is widely used in industrial and organic chemistry. [10-12] Therefore, photoreactions in presence of catalyst have recently attracted noticeable attention. TiO2 has been one of the examples which is been used in vapor phase transformation of lower alcohols at high temperatures. [13-17] Tetsuya Shishido et.al reported an effective, solvent free photooxidation of higher alcohols using molecular oxygen over Nb2O5. [18] However, very few reports are present on photooxidation and to the best of our knowledge no report is present on the effect of thickness on the optical and photocatalytic activity of niobia thin films.
The present study involves the comparative evaluation of the effect of thickness on optical properties of Nb2O5 films and photooxidation of alcohols. The films were sculptured by spin coating at different rev. /min. to obtain thickness in desired range. The optical properties like refractive index, extinction coefficient, absorbance, transmittance and their dependence on thickness of films are also investigated and