scholarly journals The Study of Optical Energy Gap, Refractive Index, and Dielectric Constant of Pure and Doped Polyaniline with HCl and H2SO4 Acids

2019 ◽  
Vol 7 (1) ◽  
pp. 47
Author(s):  
Amera G. Baker

Polyaniline (PANI) salt in its pure and doped forms find extensive applications in making devices such as polymer light emitting diodes, photovoltaic, sensors, batteries, and super capacitors. PANI salt has been synthesized successfully through chemically oxidative polymerization of aniline in the presence of hydrochloric acid (HCl) and sulfuric acid (H2 SO4 ) using ammonium peroxydisulfate as an oxidizing agent. The absorption spectra of pure PANI salt and its doped state, in HCl and H2 SO4 media, have been studied in the wavelength range from 200 to 1100 nm using ultraviolet and visible near infrared spectrophotometer. Tauc’s formula, Lambert-Beer’s relation, and Fresnel’s formula were employed in the MATLAB program to calculate the optical energy gap, refractive index, and dielectric constant. Results showed that doping with HCl and H2 SO4 acidic mediums caused a reduction in the direct energy gap of the pure PANI from 2.69eV to 2.42 eV and 2.54 eV, respectively. The reduction in optical energy gap is associated with the increase in refractive index. The refractive index (2.92) has a higher value of PANI doped with HCl. Higher refractive index values are for better-structured films.

2006 ◽  
Vol 3 (1) ◽  
pp. 56-61
Author(s):  
Baghdad Science Journal

In this research study the effect of fish on the properties optical films thickness 1200-1800 and calculated energy gap Basra direct transport permitted and forbidden to membranes and urged decreasing values ??of Optical Energy Gap increase fish included accounts optical also calculate the constants visual as factories winding down and the refractive index and reflectivity membranes also by real part and imaginarythe dielectric constant


2016 ◽  
Vol 23 (02) ◽  
pp. 1650001 ◽  
Author(s):  
ZAKI S. KHALIFA

Crystal structure, microstructure, and optical properties of TiO2 thin films deposited on quartz substrates by metal-organic chemical vapor deposition (MOCVD) in the temperature range from 250[Formula: see text]C to 450[Formula: see text]C have been studied. The crystal structure, thickness, microstructure, and optical properties have been carried out using X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), atomic force microscope (AFM), and UV-visible transmittance spectroscopy, respectively. XRD patterns show that the obtained films are pure anatase. Simultaneously, the crystal size calculated using XRD peaks, and the grain size measured by AFM decrease with the increase in deposition temperature. Moreover, the texture of the films change and roughness decrease with the increase in deposition temperature. The spectrophotometric transmittance spectra have been used to calculate the refractive index, extinction coefficient, dielectric constant, optical energy gap, and porosity of the deposited films. While the refractive index and dielectric constant decrease with the increase of deposition temperature, the porosity shows the opposite.


Author(s):  
Nahida B. Hasan ◽  
Mohammed Ahmed Mohammed

In this paper, the design of spray pyrolysis system to prepare thin films of various materials system. The study showed that films prepared with good characteristics. films were prepared from lead oxide PbO this way. The study of the optical properties of these films and through recording the absorbance spectrum and transmittance spectrum of films prepared in the wavelength range (300-1100) nm . Optical constant for thin films prepared such as absorption coefficient, the extinction coefficient , the refractive index and the optical energy gap was calculated as well. films prepared found that it has a direct energy gap value 3.1eV.


2019 ◽  
Vol 13 (28) ◽  
pp. 162-169
Author(s):  
Jinan M. Hassan Jabir

Polyaniline polymer has been prepared by chemical oxidationpolymerization method in laboratory successfully. The PANI and(PVA+PVP) as a polymer blends in different percentage (30%, 50%,70%) from Polyaniline was prepared. The sample was studies asoptical properties by UV-vis spectrophotometer at (400-700) nm.The result of optical energy gap was 2.23 eV for pure (PVA+ PVP)and with additive was increasing with increasing PANI concentrationto become (2.49 for 30% to 2.52 for 70%) PANI. The goal of thisproject is prepare triple blend polymer and study the effect when addconductive polymer (Polyaniline) on the optical properties andcalculate optical constant as energy gap, refractive index, dielectricconstant and dielectric losses for (PVA+PVP) blends.


2019 ◽  
Vol 13 (27) ◽  
pp. 83-90
Author(s):  
Nadia M. Hassan

The optical transmission and UV-VIS absorption spectra have been recorded in the wavelength range (200-1100m) for different composition of polyaniline and polyvinyl Alcohol(PVA ) blends thin films. Polyaniline was prepared in acidic medium to enhancement the solubility and processibility, The optical energy gap (Eopt) refractive index and optical dielectric constant real and imaginary part have been evaluated. The effects of doping percentage of prepared polyaniline on these parameters was discussed and the non –linear behavior for all these parameters was investigated.


2013 ◽  
Vol 724-725 ◽  
pp. 176-179
Author(s):  
T. Zhang ◽  
H. Wang ◽  
Z.Y. Zhong ◽  
C.Y. Yang ◽  
Jin Hou

Transparent conducting gallium-titanium codoped zinc oxide thin films were grown onto glass substrates with magnetron sputtering technique in ambient argon gas, and the influence of argon pressure on optical properties of the films were investigated. The refractive indexes of the films were calculated. It is found that the refractive index tends to increase with increasing the photon energy. Meanwhile, the dispersion behavior of the refractive index was analyzed in terms of the single-oscillator model and the oscillator parameters were obtained. Furthermore, the optical energy gaps were evaluated by single-oscillator model and Tauc’s relation, respectively. The values of optical energy gap estimated from single-oscillator model are in agreement with those determined from Tauc’s relation.


2001 ◽  
Vol 8 (3-4) ◽  
pp. 251-259 ◽  
Author(s):  
M. Kepinska ◽  
M. Nowak ◽  
Z. Kovalyuk ◽  
R. Murri

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