Facile synthesis and characterization of novel Gd2O3–CdO binary mixed oxide nanocomposites of highly photocatalytic activity for wastewater remediation under solar illumination

In this study, pure cadmium oxide (CdO) nanoparticles and mixed gadolinium oxide (Gd2O3)–CdO nanocomposites with different Gd2O3 contents (0–15%) were synthesized by a facile precipitation technique followed by calcined treatment. The X-ray diffraction analysis illustrated that all samples had high cubic-phase purity and a good crystallinity. Further support for the formation of highly pure CdO and Gd2O3 phases was obtained via infrared spectroscopy. The morphologies of pure CdO and mixed Gd2O3–CdO nanoparticles were probed by scanning electron and transmission electron microscopy, which demonstrated that the collected samples consisted of individual semi-spherical shaped entities of different particle sizes (23–31 nm). The optical band gap of the developed samples was computed based on the Tauc equation and showed a decrease from 3.41 to 2.75 eV upon increasing the Gd2O3 content …