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New proposed optical polymeric systems of PVAL/Cu particles have been synthesized by casting proceed to stand their NL (Nonlinear)/L (Linear) optical properties for various optical applications. Herein, the structure of the composites with various wt% of Cu was analyzed by the diffraction of X-ray (XRD) and FTIR. The semi-crystalline nature of PVAL has been influenced by Cu concentration as presented in XRD and Gaussian fitting. FTIR results confirm the strong interaction between Cu and polymer via the main hydroxyl group of the matrix. The morphological surfaces of pristine and doped PVAL have been measured. Optical measurement shows a redshift of the absorption edge. Moreover, the indirect transition bandgap decreased gradually with the Cu-level. This reflects the presence of localized states in the prohibited band facilities the electrons transition from HOMO to LUMO. The extinction coefficient and Urbach energy of the films have been enhanced. The ε o (static) and ε ∞ (high-frequency) dielectric variables are calculated. NL/L refractive index and susceptibility are estimated from the bandgap values. The optical limiting of the composite films has been tested using a green diode laser and He-Ne laser. The PVAL sample with high Cu wt% is an optical system capable of different technical applications, such as solar cells, optoelectronic devices, electronic apparatus, and optical filters.

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New composite films based on ceramic/polymeric matrix materials were synthesized using facile casting procedures for different optical devices. Herein, the composite comprises a semi-crystalline polymer (Polyvinyl alcohol, PVAL) embedded with various weight percentages of PbTiO3. The structure and surface morphology change of PVAL were studied via XRD (Diffraction of x-ray) and SEM (Microscopy of Scanning Electron) analysis. The interactions between PVAL and PbTiO3, via the matrix’s hydroxyl group, demonstrate a significant reduction in polymer crystallinity. Different parameters, such as internal strain, dislocation density, and crystallite size, were estimated from the XRD Gaussian fitting. SEM images show that the particles’ agglomeration increased on the composite’s surface with the doping ratio, which can influence the PVAL optical properties. The energy of the bandgap is estimated using absorption fitting and Tauc’s relations. Nonlinear and refractive indices parameters- energy gap relations were studied. The nonlinear parameters χ (3) and n 2 increased with rising the percentage of PbTiO3 in the PVAL matrix from 0.935 × 10−12 esu to 1.978 × 10−12 esu, and 1.67 × 10−11 esu to 3.29 × 10−11 esu. Moreover, the high-frequency dielectric ( ε ∞ ) changes from 4.421 to 5.125. The behavior of optical limiting for the composites shows a decrease of He-Ne and green laser power. The present results indicate that the polymeric/ceramic films can be promising materials for laser CUT-OFF, optical fibers, and micro-optics applications.

Hybrid polymer films of polyvinyl pyrrolidone (PVP)/polyvinyl alcohol (PVA) embedded with gradient levels of Bi-powder were prepared using a conventional solution casting process. XRD, FTIR, and SEM techniques have been used to examine the micro/molecular structure and morphology of the synthesized flexible films. The intensities of the diffraction peaks and transmission spectrum of the PVP/PVA gradually declined with the introduction of Bi-metal. In addition, filler changes the microstructure surface of the pure film. The modification in the microstructure leads to an enhancement in the optical absorption characteristic of the blend films. The indirect allowed transition energy was calculated via Tauc’s and ASF (Absorption Spectra Fitting) models. The decrease in the hybrid film’s bandgap returns to the localized states in the forbidden region, which led the present films to be suitable for photo-electric, solar cell, etc., applications. The relation between the transition energy and the refractive index was studied. The enhancement in the refractive index with Bi-metal concentrations led to use the as-prepared films in optical sensors. The rise of Bi-metal concentrations leads also to the improvement of the nonlinear susceptibility and refractive parameters. The optical limiting characteristics revealed that the higher concentration dopant films reduce the light transmission intensity which is appropriate for laser attenuation and optical limiting in photonic devices. The results suggest that hybrid films are promising materials in a wide range of opto-electronic applications.