UV Light‐Driven Photocatalytic Performance of CeO2 and Co Ion‐Doped CeO2 Nanoparticles: High‐Efficiency Electrochemical and Chromaticity Blue LED Application

Abstract The study assesses the efficacy of CeO 2 nanoparticles synthesised via the hydrothermal method for UV‐induced catalytic activity in decomposing cobalt complexes. Various analyses, including X‐ray diffractometry (XRD), Raman spectroscopy, scanning electron microscopy (SEM), high‐resolution transmission electron microscopy (HR‐TEM), and UV‐Vis spectrophotometry were employed to investigate the impact of cobalt on cerium oxide's morphology, optical, electrochemical, and microstructural characteristics. The XRD analysis revealed a cubic structure in the fluorite‐type pattern, primarily oriented along the (111) direction. Raman spectroscopy supported these findings, identifying an active mode peak at 464 cm −1 and indicating the presence of F 2g cubic fluorite. SEM imaging displayed cleavage and uniform, densely packed grains. Elemental analysis confirmed the presence of Ce, O, and Co, corroborated by X‐ray Photoelectron Spectroscopy (XPS) data. Optical measurements indicated a band gap starting at 3.03 eV, which decreased with increasing Co ratio, reaching 2.9 eV at 4 % cobalt incorporation. Furthermore, cyclic voltammetry experiments demonstrated that Co‐doped samples exhibited enhanced ion storage capacity. These comprehensive analyses underscore the potential of Co‐doped CeO 2 nanoparticles for UV‐induced catalytic activity, offering valuable insights into their structural and functional properties.