NbO nanoparticles decorated with magnetic ferrites for wastewater photocatalytic remediation.

Nanotechnology has been studied on environmental remediation processes to foster greater photocatalysts efficiency and reuse in wastewater. This study investigated the photocatalytic efficiency and viability of niobium pentoxide (NbO) nanoparticles decorated with magnetic ferrite (cobalt ferrite (CoFeO) or magnesium ferrite (MgFeO)) for atrazine photodegradation. Thus, the decorated NbO was synthesized by the polymeric precursor method, forming nanoparticles with sizes ranging from 25 to 50 nm. Nanocomposite elementary analyses showed a homogeneous distribution of elements on all particles surface. Efficient magnetic saturation was observed for pure CoFeO (53 emu g) and MgFeO (19 emu g) nanoparticles, promoting the magnetic removal of NbO:CoFeO and NbO:MgFeO nanocomposites. Photocatalytic assays showed 88% efficiency for atrazine photodegradation with all nanomaterials, which represented a 21% increase compared to photolysis in the 1st cycle. The magnetic nanocomposites when applied to a 5th cycle maintained the atrazine photodegradation activity. In this way, magnetic NbO-based nanocomposites decorated with ferrite nanoparticles showed an efficient photocatalytic response, in addition to posterior magnetic removal from the aqueous medium. Therefore, the evaluated magnetic NbO nanocomposites may be an alternative to enhance the wastewater removal process and foster the reuse in advanced oxidative processes.