Effect of Ag‐Nanoparticles Doped in Polyvinyl Alcohol on the Structural and Optical Properties of PVA Films

Abstract

The effect of silver nanoparticles doped in PVA on the structural and optical properties of composite films is studied experimentally. Samples are PVA films of 0.14 mm thickness doped with different sizes and concentrations of silver nanoparticles. Structural properties are studied using X-ray diffraction and FTIR spectrum. Using the reflectance and transmittance of samples, the effect of doped nanoparticles and their concentration on optical parameters of PVA films include absorption coefficient, optical bandgap energy, complex refractive index, complex dielectric function, complex optical conductivity, and relaxation time is extracted and discussed. The dispersion of the refractive index of films in terms of the single oscillator Wemple-DiDomenico (WD) model is investigated and the dispersion parameters are calculated. Results show that by doping silver nanoparticles in PVA, number of Bragg’s planes in the structure of polymer and its crystallinity are increased noticeably. Ag–O bonds are formed in the films and the bandgap energy of samples is decreased. Calculations based on WD model confirm that by doping nanoparticles, the anion strength of PVA as a dielectric medium is decreased.

Enhancing the Optical Properties of Polyvinyl Alcohol by Blending It with Polyethylene Glycol

“…6a the PVA refractive index increases with increase of the content of PEG in the PVA/PEG blends up to PVA/PEG 79/21 wt% above which it decreased. The increase of the refractive index of the PVA/PEG blends compared to that of the pure PVA can be an indication of an increasing density of the blends which results in developing the interatomic spacing according to the famous formula of the Clausius-Mossotti [24,25]. The loss in the electromagnetic energy, as a result of scattering and absorption per unit thickness, when the electromagnetic wave propagates through the material, is described by the extinction coefficient k. The obvious variation of the extinction coefficient k with wavelength, especially at high wavelengths as shown in Fig.…”

“…On the other hand, the imaginary part is responsible of the dissipative rate of electromagnetic wave propagation in medium. The real and imaginary parts of dielectric constant are described by the following equations in terms of the refractive index and extinction coefficient [24]:…”

Optical and structural investigation of synthesized PVA/PbS nanocomposites

“…The wide range of PVA applications can be even more extended by incorporation of filler into PVA matrix, because well-dispersed filler may enhance various physical properties of the host polymer [9]. Since PVA can effectively protect the NPs from aggregation [10,11], numerous reports in the literature show attempts for synthesis and characterization of different NPs doped in PVA film [12][13][14][15][16][17]. The characteristics of these nanocomposite films can be manipulated by varying the particle size, shape, and concentration of NPs.…”

Influence of Magnetic Field on Silver Nanoparticles Synthesized by Laser Ablation

“…The spectrum shows a broad peak at 3421.48 to 3448.49 cm -1 in the high frequency area together with a sharp peak at 1635.52cm −1 , corresponding to the stretching and bending vibration of OH groups of water molecules [17,18]. The absorption peaks corresponding to 690 cm -1 are representing Ag-O deformation [19]. The peak that belongs to the vibration of the Ag-Ag metallic bonds cannot be seen in this graph because the FTIR used the mid-infrared ray (4000-400 cm -1 ) that is not suitable to measure the vibration frequency of metal-metal bonds [20].…”