Structural and optical properties of PVB/ZnS nanocomposite films

Abstract

Herein, three nanocomposite films based on polyvinyl butyral (PVB) and zinc sulfide (ZnS) have been synthesized via the solution-casting technique. This study, for the first time, investigated the effect of ZnS nanoparticles (NPs) with different percentages (0, 1, 2, and 3 wt.%) on the structural, linear/non-linear optical, and dispersion properties of PVB/ZnS nanocomposite films. XRD study confirms the successful synthesis of ZnS NPs and ZnS-reinforced PVB nanocomposite films. The bandgap for ZnS-reinforced PVB nanocomposite decreases from 5.54 eV to 4.95, 4.85, and 4.78 eV with increasing the ZnS percentage. Conversely, The band tail increased from 0.73 eV of the pure PVB to 0.83, 0.82, and 0.91 eV with increasing the ZnS percentage. The optical conductivity increased from 0.8 × 10¹¹ s/cm² to 2.45 × 10¹² s/cm². Also, the N/m* value increases from 0.23 × 10³⁹ kg⁻¹ m⁻³ to 0.28 × 10³⁹ kg⁻¹ m⁻³ with increasing ZnS contents. The optical mobility also increased from 0.067 × 10¹³ s⁻¹ for PVB to 0.081 × 10¹³ s⁻¹ for PVB/ZnS-III film. The values of χ⁽¹⁾ and χ⁽³⁾ increase as the influence of incorporating ZnS concentration increases. These results confirm that the ZnS-reinforced PVB nanocomposite films are candidates for non-linear optical applications and are more valuable for optoelectronic devices than pure PVB.