Structural, Optical, and Photocatalytic Properties of CdO/La2O3/PVP Nanocomposites by Microwave Irradiation Method

This study explores the structural, morphological, optical and photoluminescent properties of pure CdO, CdO/La₂O₃, and CdO/La₂O₃/PVP nanocomposites synthesized via the microwave irradiation method. XRD analysis confirms the face—centered cubic phase of CdO and the successful incorporation of La₂O₃ and PVP, evidenced by changes in lattice parameters and reduced crystallite sizes. Fourier transformed infrared spectroscopy (FTIR) analysis detects functional groups associated with La₂O₃ and PVP, confirming their integration into the CdO matrix. TEM reveals smaller particle sizes, improved dispersion and enhanced crystallinity in the composites. UV-Vis spectroscopy shows a bandgap increase from 3.4 eV (CdO) to 4.2 eV (CdO/La₂O₃/PVP), attributed to the Burstein–Moss effect and structural changes. PL studies indicate enhanced multi-band emissions and defect related transitions, suggesting improved charge separation and reduced recombination. Under UV irradiation, CdO/La₂O₃/PVP exhibits the highest photocatalytic degradation efficiency for MB dye (65.77% in 120 min), outperforming CdO/La₂O₃ (48%) and pure CdO (22%) due to smaller particle size, more active sites, and better charge carrier separation. These results demonstrate the potential of CdO-based nanocomposites in photocatalysis, optoelectronics and energy harvesting applications.