Preparation and Optical Properties of PVDF-CaFeO Polymer Nanocomposite Films.

In this work, a synthesis technique for highly homogeneous PVDF-CaFeO polymer films direct from solution was developed. The structural characterizations were conducted using XRD, FTIR, and ESEM experimental techniques. The XRD characteristic peaks of CaFeO nanoparticles revealed a polycrystalline structure. The average crystallite size for CaFeO was calculated to be 17.0 nm. ESEM micrographs of PVDF nanocomposites containing 0.0, 0.25, 0.75, and 1.0 wt% of CaFeO showed smooth surface topography. The direct E and indirect E band gap energies for the PVDF-CaFeO nanocomposites were decreased with the additions of 0.0-1.0 wt% CaFeO. In addition, the refractive index () increased from 3.38 to 10.36, and energy gaps (E) decreased from 5.50 to 4.95 eV. The nonlinear refractive index (n) for the PVDF-CaFeO nanocomposites was improved with the addition of CaFeO nanoparticles, exceeding those reported in the literature for PVC, PVA, and PMMA nanocomposites. Therefore, the PVDF-CaFeO nanocomposites are expected to take the lead in optoelectronic applications because of their unusual optical properties.