Time-Dependent Hydrothermal Synthesis of La2O3 NPs for Effective Catalytic Activity of Ionic Dye

Lanthanum oxide was successfully synthesized by hydrothermal method by varying the reaction time such as 6, 12, and 24 h. In XRD, study confirms the presence of a hexagonal structure, and the phase remains the same at different times; the main goal is to assess the average crystallite size of prepared La₂O₃ nanoparticles, which was found in the range of 6 to 8 nm. An interesting observation from the XRD data was the apparent increase in crystalline nature as the synthesis time was extended. The UV–Vis spectroscopic studies show a change in the band gap when the reaction time is changed. The morphology analysis shows that the image revealed that the particles formed were agglomerated and formed a spherical shape, with diameters ranging between 35 and 86 nm. When tested for photocatalytic activity, the La₂O₃ nanoparticles show a degradation of methylene blue dye when the time varies. Remarkably, the nanoparticles synthesized exhibited a profound ability to degrade the dye, with an efficiency rate hitting as high as 89% under halogen light illumination.