Fabrication of MoO₃/rGO/Au composite for increased photocatalytic degradation of methylene blue

Water line purification and wastewater treatment have become challenging in the fast-growing industry, infrastructure, textile, manufacturing world, etc. with this challenge, photocatalysis has gained substantial attention as an environmentally friendly process on which researchers are working aggressively and, in this progress, two-dimensional (2D) are in focus because of their good photocatalytic ability. Therefore, in this study, we present the synthesis of one such ternary composite material comprising molybdenum trioxide nanorods (MoO₃NR), reduced graphene oxide (rGO) and gold nanoparticles (AuNR), with a specific focus on its enhanced photocatalytic performance. The ternary composite is prepared via a combination of in situ hydrothermal and laser ablation methods allowing for precise control over the growth and integration of the constituent materials. The structural and morphological properties of the MoO₃ nanorods, rGO and Au ternary material were systematically characterized using various techniques, including UV-vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). The obtained results suggest the successful formation of a composite, revealing the presence of uniformly dispersed MoO₃ nanorods on the rGO sheets and evenly distributed Au nanoparticles throughout the structure. Photocatalysis evaluations conducted to assess the material performance under visible light irradiation exhibited significantly enhanced methylene blue degradation efficiency of 85.91% in 90$$min in comparison with individual MoO₃ nanorods and rGO counterparts. The improved efficiency can be attributed to the combined effects arising from the integration of MoO₃ nanorods, rGO and Au nanoparticles, which facilitate efficient light absorption, charge separation and catalytic reactions, which in turn reduces electron–hole recombination and improve photocatalytic performance. Also, the tunable morphology and collective effects of MoO₃ nanorods, rGO and Au offer new avenues for designing highly efficient and stable photocatalytic materials.