Vanadium-Doped Magnesium Oxide Nanoparticles Formation in Presence of Ionic Liquids and Their Use in Photocatalytic Degradation of Methylene Blue

Magnesium oxide (MgO) is one of the metal oxides having unique properties with numerous potential industrial applications. In this study, MgO and vanadium-doped MgO nanoparticles were synthesized by sol–gel method in 1-butyl-3-methylimidazolium tetrafluoroborate [BMIM][BF4] and 1-octyl-3-methylimidazolium tetrafluoroborate [OMIM][BF4] ionic liquids. Vanadium-doped MgO nanoparticles exhibited nanosphere and nanorod morphologies with 40–80 nm in particle size, primarily due to the influence of ionic liquids as demonstrated by high-resolution scanning electron microscopy and transmission electron microscopy. Characteristics of nanoparticles were also studied by thermal gravimetric analysis, X-ray diffraction and energy-dispersive X-ray spectroscopy. Photodegradation ability of synthesized nanoparticles was evaluated for methylene blue (MB) in specially designed UV reactor. Photodegradation is found to be dependent on doping, and particle characteristics change due to the influence of ionic liquid. The ionic liquid-assisted vanadium-doped MgO nanoparticles showed good reusability under UV irradiation and MB degradation ability under visible light.