الفهرس 
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Abstract
The main objective of this work is to fabricate infrared sensor based on polyaniline/polyvinylidene fluoride (PANI/PVDF) blend film or polyaniline/polyvinylidene fluoride/barium titanate (BaTiO3) composite materials. Polyaniline (PANI) doped with dodycylebenzen sulfonic acid (DBSA) or camphor sulfonic acid (CSA) is prepared chemically. PANI-DBSA/PVDF blend films with different weight percentages 0, 5, 10, 15, 20, 25 wt.% of PANI-DBSA are cast using dimethyformamide (DMF) as a co-solvent. PANI-CSA/PVDF/BaTiO3 composite films with different weight percentages 0, 25, 50, 75 and 100 wt.% of BaTiO3 are prepared. The prepared films are characterized by scanning electronic microscope (SEM) and X-ray diffraction (XRD). Pyroelectric properties and electrical measurements such as current-voltage curves, electrical conductivity, and pyroelectric coefficient for the PANI-DBSA/PVDF blend films and PANI-CSA/PVDF/BaTiO3 composite films are performed. In addition, the pyroelectric properties such as responsivity, noise equivalent power, and detectivity for the prepared samples are measured and investigated. Electrical chopped frequency circuit is built to characterize the pyroelectric sensor. The voltage responsivity, noise equivalent power and detectivity of the PANI-DBSA/PVDF and PANI-CSA/PVDF/BaTiO3 blend films sensor are measured.Pristine PVDF film cast from DMF has shown a regular smooth structure-less surface. The morphology of PANI-DBSA/PVDF blend film with 5 wt.% of PANI indicates small agglomerations of PANI phase on the surface of the PVDF film with fibular structure. The morphology of PANI-DBSA/PVDF blend film with 10 wt.% of PANI nano-fibers with average aspect ratio of 5 and enhanced to 20 for 15 wt.% , 20 wt.% and 25 wt.% of PANI.For PANI-CSA/PVDF/BaTiO3 composite films, PVDF appears as block structure; randomly dispersed with aspect ratio of 4 due to the effect of CSA dopant which may prevent the agglomeration of PANI for 0 wt.% of BaTiO3. For 25 wt.% of BaTiO3, the PANI appears as leafs structure. At 50, 75, and 100 wt.% of BaTiO3 the aspect ratio of PANI increases to 6, 12, and 14, respectively.It is found that, the addition of PANI to PVDF enhances the crystallization of the PVDF in β-phase and the XRD spectra show an increase in the intensity of β-phase and a decrease in the intensity of the α-phase. XRD patterns of the PANI- CSA/PVDF/BaTiO3composite films show an enhancement in the degree of crystallinity with the increase of BaTiO3weight percentages.The behavior of the electrical conductivity of PANI-DBSA/PVDF blend films and PANI-CSA/PVDF/BaTiO3 composite films with different weights percentage of PANI and BaTiO3 is evaluated according to the percolation theory.The conductivity of the pristine PVDF film at room temperature found about 8.22×10-11 S/cm while for 25 wt.% of PANI is about 1.46×10-8 S/cm. Experimentally, the percolation threshold is found to be 5 wt.%. In addition, for PANI-CSA/PVDF/BaTiO3 composite films the conductivity increases from 4.08×10-8 S/cm for 0 wt.% of BaTiO3 to 8.84×10-6 S/cm for 100 wt.% of BaTiO3.The addition of PANI with different weight percentages to PVDF enhances the pyroelectric coefficient from 1.5×10-8 C/m2°C to 6.5×10-5 C/m2°C at room temperature for pristine PVDF and 25 wt.% of PANI respectively. PANI-DBSA/PVDF blend film with 10 wt.% of PANI exhibits the best pyroelectric parameters. The voltage responsivity, detectivity, and noise equivalent power are equal to 149 V/W and 9×103 cm.Hz1/2/W, and 5×10-5 W/√Hz respectively. For samples with higher percentage of PANI, the values of pyroelectric parameters are degraded due to the increase in the intensity of α-phase as indicated in the XRD patterns.The addition of BaTiO3 enhances the values of pyroelectric parameters from 2.43×10-5 C/m2°C to 1.45×10-4 C/m2°C for 0 wt.% and 100 wt.% of BaTiO3. PANI-CSA/PVDF/BaTiO3 composite film with 25 wt.% of BaTiO3 exhibits the best pyroelectric parameters. The voltage responsivity, detectivity, and noise equivalent power for this sample are equal to 152 V/W, 1.3×103 cm.Hz1/2/W, and 4×10-4 W/√Hz respectively. For samples with higher percentages of BaTiO3, the values of pyroelectric parameters are decreased due to the percentages of agglomerated cluster of unreacted BaCO3 as indicated using the SEM photos and XRD patterns.