Novel UiO-66(Ce)/CdS/g-C3N4 ternary nanocomposite with boosted photoactivity in the degradation of the dye rhodamine B

Abstract

Metal-Organic Frameworks (MOFs) are a category of porous material recognized for their tuneable structures and high surface areas, making them promising candidates for various applications, including photocatalysis. Among these, UiO-66(Ce) has attracted significant attention from the scientific community due to its impressive redox capabilities, effective ligand-to-metal charge transfer, and effecient charge-hole separation. This study reports the successful synthesis of novel ternary nanocomposite that combined UiO-66(Ce) with CdS and g-C 3 N 4 . The physicochemical characterization was addressed using XRD, XPS, FE-SEM-EDS, EDS mapping, FTIR, TGA, N 2 adsorption-desorption isotherms, PL and DRS-UV-vis techniques. These studies confirm the effective formation of heterojunction nanocomposite materials. The ternary nanocomposites were evaluated as photocatalysts in the degradation of the dye rhodamine B, achieving degradation rates of 97.5 % and 99.5 % within 120 minutes under visible light and sunlight systems, respectively. These rates significantly surpassed the photocatalytic performance of the individual components and their binary combinations. The results highlight significant synergistic effects within the heterostructures, enhancing the transfer of charges across interfaces and bettering the separation of light-generated electron-hole pairs. The produced active intermediates, including hydroxyl radicals ( • OH), superoxide anions ( • O 2 - ), and holes (h + ), exhibited nearly equivalent quenching effects. Furthermore, the synthesized ternary nanocomposite demonstrated remarkable stability and recyclability, maintaining considerable performance over at least five cycles. A potential reaction mechanism for the photocatalytic process has also been suggested.