Synthesis, characterization, and anti-cancer activity evaluation of Ba-doped CuS nanostructures synthesized by the...

Pure and barium (Ba)-doped copper sulfide nanostructures were synthesized by the chemical co-precipitation method at room temperature. The pure and Ba-doped CuS nanoparticles have been compared structurally, morphologically, and optically using X-ray diffraction (XRD), transmission electron microscopy (TEM), total reflection X-ray fluorescence (TXRF), diffuse reflectance spectroscopy (DRS) and photoluminescence (PL) spectroscopy. The results of X-ray diffraction (XRD) showed that the CuS nanostructures have a hexagonal structure with crystallite sizes ranging from 15.14 to 16.69 nm. TXRF was used to confirm the presence of Ba-doped CuS. Diffuse reflectance spectroscopy (DRS) analysis revealed that the bandgap energy of the CuS nanostructures increased with increasing Ba doping concentration (1.38 to 1.82 eV). Optical constants such as absorption coefficient, extinction coefficient, and refractive index were calculated. A photoluminescence study of CuS was carried out. One photoluminescence (PL) band was found at 826 nm (1.5 eV) at room temperature and was attributed to band-to-band (BB) and band-to-impurity recombination. The MTT assay was used to measure the cytotoxicity effect on human lung cancer cell lines (A549). The results showed that CuS nanostructure with 5% Ba doping exhibits more toxicity than other samples, with an IC₅₀ of 8.46 g ml^-1 being the most significant concentration, suggesting that it may be a promising cancer treatment agent.