SYNTHESIS AND CHARACTERIZATION OF rGO/Gd2TiO5 NANOCOMPOSITE FOR PHOTODEGRADATION AND ANTICANCER ACTIVITY

Abstract: A novel nanocomposite of reduced graphene oxide supported Gd2TiO5 was successfully synthesized using a sol-gel method. The synthesized materials were characterized using XRD, FT-IR, SEM with EDAX, UV-DRS, HR-TEM, BET, and XPS techniques. Crystalline sizes were determined using XRD and found to be 26.7, 36.0, 55.8 and 58.1 nm for rGO, TiO2, Gd2TiO5, and rGO/Gd2TiO5, respectively. FT-IR analysis also revealed the presence of distinctive peaks that corresponded to the vibrations of Ti-O, Gd-O, and rGO. The morphology studies revealed the shapes of the synthesized nanomaterials. Specifically, rGO exhibited a sheet-like structure, TiO2 appeared as agglomerates, Gd2TiO5 formed irregularly shaped agglomerates, and the rGO/Gd2TiO5 composite showed Gd2TiO5 dispersed over the rGO surface, as confirmed by SEM analysis. EDAX spectra further supported the presence of C, O, Ti, and Gd elements in the nanocomposite, which was consistent with the XPS results. UV-DRS analysis was used to identify the band gap values as 3.00, 3.06, 3.10, and 3.08 eV respectively for rGO, TiO2, Gd2TiO5, and rGO/Gd2TiO5. The surface area (~25.47 m²/g) and pore volume (~0.0820 cm³/g) were evaluated using BET analysis. The adsorption of dye molecules on to the catalyst surface is favourably affected by the measured surface area and pore volume, which are beneficial for improved light absorption. Photoactivity was assessed through the degradation of Methylene blue (MB) dye under solar radiation. The results showed that the prepared Gd2TiO5 and rGO/Gd2TiO5 photocatalysts effectively photodegraded the organic pollutants in wastewater when exposed to sunlight. The development of this novel photocatalyst offers promising potential for treating organic contaminants in water. In addition, in - vitro studies have revealed that rGO/Gd2TiO5 nanocomposite shows a strong anticancer potential against A549 lung cancer cells. The treatment through the nanocomposite produced morphological transformations of irregular shapes and shrinkage in A549 cells. Thus, the increased anticancer effect of the rGO/Gd2TiO5 composite can be attributed to its low band gap energy (3.08 eV) and large surface area (25.47 m²/g) which facilitate generating the reactive oxygen species (ROS) that are toxic to cancer cells. The development of this new photocatalyst with double function holds great promise for the further treatment of organic contaminants from water and fighting cancer cells.