Abstract This study loaded Bi/Bi 2 O 3 on the surface of reduced graphene oxide (rGO) to perform a two-step facile synthesis of rGO@Bi/Bi 2 O 3 as a bismuth-based nanocomposite. First, Bi/Bi2O3 nanocomposites were synthesised via a solvothermal process using Bi(NO 3 ) 3 5H 2 O as the Bi 3+ precursor and dimethyl sulfoxide (DMSO) as the solvent. Second, we exfoliated rGO in water to functionalise Bi/Bi2O3 with a few layers of rGO. Obtained nanocomposites were characterised with scanning electron microscopy and X-ray diffraction. We also measured the nanocomposites’ photocatalytic activity using cationic dyes, specifically methylene blue (MB) and rhodamine B (RhB). Additionally, ultraviolet-visible spectroscopy was used to determine the optical properties of rGO@Bi/Bi 2 O 3 . Photodegradation was recorded under differing durations of exposure to visible light. Reaction rates were recorded at 14.6 × 10 –4 min −1 and 22.2 × 10 –3 min −1 for MB and RhB, respectively, while photodegradation efficiency was logged at 17% and 81%.