Facile synthesis of PVDF/SnO2 nanocomposite thin films for optoelectronic applications

Thin films of pure polyvinylidene fluoride (PVDF) and PVDF/SnO2 nanocomposites were fabricated by sol ̶gel spin coating method. The weight percentage of SnO2 in PVDF matrix was varied from 0.25%, 0.5%, and 1%. X-ray diffraction graphs exhibited the rutile structure of SnO2. Scanning electron microscope confirmed densely packed morphology of pure PVDF and dispersion of SnO2 agglomerated spherical particles in PVDF matrix. The presence of all constituent elements in a specific ratio was confirmed from energydispersive X-ray spectroscopy. Furthermore, optical properties were taken by ellipsometry in terms of ψ (Psi) and Δ (Delta) values which were acquired through the specific fitting model, and these modeled values were fitted with the experimental values. The real part of the dielectric function showed a high refractive index at minimum energy for pure PVDF as compared to PVDF/SnO2 nanocomposite films whereas the imaginary part exhibited significantly high absorption spectra at minimum energy for pure PVDF and vice versa for PVDF/SnO2 films. Furthermore, pure PVDF film showed high absorption which increased with the increase of energy of interacting light but decreased with the incorporation of SnO2 nanoparticles. The entire observation exhibited that PVDF/SnO2 nanocomposite thin films can be utilized for optical devices like transpicuous conductors and chemical sensors etc.