Tailoring the optical properties (linear and nonlinear) of triple blended polymers via reinforcement of interchangeable proportions of mixed (SnO₂ and NiO) nanofillers for promising applications

The recognition and characterization of semi-biopolymeric CMC/PVP/PEG blends through the incorporation of high purity NiO and SnO₂ nanofillers with different interchangeable proportions have been investigated. The sol–gel technique was used for preparing NiO and SnO₂ nanofillers, while undoped and doped blends were prepared by the casting technique. A homogeneous distribution of the nanofillers within CMC/PVP/PEG blends was assessed by scanning electron microscopy (SEM) and field emission mapping. The structure of the resulting undoped and doped blends were studied by x-ray diffraction (XRD). The FTIR spectroscopic technique was used to evaluate the effect of incorporated nanofillers on the blend's structure. The UV–Vis spectrophotometer was used to study the optical properties of the prepared blends. Calculations were based on the well-known single oscillator model. The transparency of the resulting samples was reduced by 30% due to the 100% NiO nanoparticles. The energy gap (E_g) values were determined using two different approaches. A gradual decrease in E_g values from 4.8 to 4 eV with the nanoparticle doping sequence from 100% NiO to 100% SnO₂ with a step (± 25%), has been noticed. The effect of doping proportions on other optical parameters such as: extinction coefficient, refractive index, real and imaginary dielectric parameters, optical conductivity, VELF, and SELF functions has been investigated. The third-order nonlinear susceptibility χ⁽³⁾ and the nonlinear refractive index (n₂) were calculated based on the linear optical parameters. The improvement in the linear and nonlinear parameters suggested its usage as a promising candidates for future optoelectronics manufacturing.