Bismuth/bismuth oxide-incorporated reduced graphene oxide nanocomposite: Synthesis, characterisation, and photocatalytic activity

Abstract

This study loaded Bi/Bi2O3 on the surface of reduced graphene oxide (rGO) to perform a two-step facile synthesis of rGO@Bi/Bi2O3 as a bismuth-based nanocomposite. First, Bi/Bi2O3 nanocomposites were synthesised via a solvothermal process using Bi(NO3)3 5H2O as the Bi3+ 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/Bi2O3. 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%.