Facile green synthesis of lanthanum oxide nanoparticles: their photocatalytic and electrochemical applications

Green synthesis is a reliable way to synthesize metal oxide nanoparticles (NPs) without affecting the environment. Plant extracts act as reducing agents that favor the synthesis of NPs. In this study, jackfruit aqueous extract was used as a fuel in the solution combustion synthesis of lanthanum oxide (La₂O₃) NPs. X-ray diffraction (XRD) confirmed the formation of the hexagonal structure of La₂O₃ NPs. The scanning electron microscope (SEM) and energy dispersive X-ray (EDS) spectrum confirm the needle-shaped morphology and purity of the La₂O₃ NPs, respectively. Furthermore, La₂O₃ was utilized as a photocatalyst for the photodegradation of methylene blue dye under visible light radiation, demonstrating high efficiency within 90 min of light irradiation. The electrochemical characteristics of La₂O₃ were studied using a carbon paste electrode in a 0.1 M HCl solution. These La₂O₃ samples exhibited superior sensitivity in cyclic voltammetry tests towards the detection of ascorbic acid and lead nitrate. Consequently, La₂O₃ holds potential for applications in electrochemical sensor technology.