Synthesis, Structural, Optical, and Electrical Characterization of Bio-Chitosan/Na0.5Bi0.5TiO3 Composite Thin Films Materials

The purpose of this research work was to synthesis bio-derived nanocomposite films by incorporating Na0.5Bi0.5TiO3 (NBT) nanoparticles into Chitosan matrix. The NBT nanoparticles were synthesized using a traditional solid-state technique. Then, through a solution casting approach, flexible composite films were fabricated using Chitosan polymer. The morphology and structural assessments were carried out utilizing scanning electron microscopy (SEM), X-ray diffraction and fourier transform infrared technique. The SEM micrographs showed that NBT nanoparticles were randomly distributed and interconnected with other particles, forming interconnected grains with substantial interspaces within the matrix. The spectral response between 300 and 800 nm of the composites is mainly governed by light scattering of NBT particles with diameter sizes in the 100 - 400 nm range and the bandgap of the NBT phase. The dielectric studies demonstrated that the composite films exhibited higher dielectric values compared to the pure Chitosan film. Besides, the increase of NBT amount was found to increase the dielectric values. Additionally, local piezoelectric measurements reveal the expected piezoelectric and ferroelectric behavior for the NBT particles dispersed into the polymer matrix, as locally probed by Piezoresponse Force Microscopy. The studied system bears interest for advanced biocompatible opto- and piezo-electric materials.