Sulfide base Silver, Copper, and Cadmium nanoparticles optical and structural characteristics

Chemical colloidal solutions based on water as a green solvent were employed for the synthesis of PVA/CdS, PVA/CuS and, PVA/Ag₂S nanocomposites. The presence of PVA acted as a capping agent and was used for polymer stabilizing. Then morphological studies followed by XRD and AFM revealed monolithic and small size nanoparticles (NPs) in the range 20-27 nm. Uv-Vis absorption spectra of samples showed decreasing absorption from NIR to visible region amount except CuS that had a minimum around 550 nm. The bandgap of samples measured using absorption data was around 2-2.5 (eV). Nonlinear optical properties including nonlinear refractive index n₂ and nonlinear absorption coefficient β of synthesized NPs measured by Z-scan technique under 632.8 nm wavelength He-Ne CW laser. PVA/ Ag₂S nanoparticles displayed reverse saturable absorbance (RSA) and self-defocusing while PVA/CdS and PVA/CdS displayed saturable absorbance and self-focusing behavior under the same condition. Concerning other similar researches, this work covered more vast types of nanoparticles and obtained and compared the differences and possible applications for each NPs.