Synthesis, structure, and optical studies of nanocomposites based on copoly (arylidene cyclohexanone) and CdS nanoparticles for photocatalytic and white LED applications

Abstract

For various optical applications, the fabrication of nanocomposites of co-polyarylidene (cyclohexanone/4-tertiary butyl cyclohexanone) CoP6 with various-sized cadmium sulfide CdS nanoparticles via in situ polymerization has been investigated (CoP6-CdS NCs). Several techniques like FT-IR, XRD, XPS, SEM, TGA, TEM, UV–vis, and fluorescence emission have been used to investigate, characterize, and study nanocomposites' structural and optical characteristics. The optical band gap of NCs was found to have a slight redshift, from 2.81 to 2.71 eV, with no alteration to the absorption peak. The crystallinity and phase formation were studied by XRD, which showed that the produced NCs with larger (CdS) particles retain some crystalline structure. The NCs generated were characterized by SEM and TEM, revealing their aggregation inside the polymer matrix. The thermal stability of the produced nanocomposites varies with the size of the nanoparticles, with larger NPs being less stable than CoP6 in the first two stages of thermal degradation and smaller NPs showing better stability in the first stages. Their outstanding optical properties make them be used in solar cells and photocatalysts. According to the photophysical analysis, new CoP6-CdS NCs have excellent optical quality with 95% optical transparency and low absorption in the visible region; the light transmittance in the UV region is reduced as the size of the CdS NP increases. There is a potential for using CoP6-CdS NCs in white LED applications in the visible region by varying CdS nanofiller size. However, because the nanocomposites exhibit enhanced absorption in the UV region, they can be used as a material for UV protection.