ZnO/ZnBi2O4 nanocomposites with p-n heterojunction as durable visible-light-activated photocatalysts for efficient removal of organic pollutants

Novel ZnO/ZnBi2O4 nanocomposites were fabricated by integrating ZnO with ZnBi2O4 nanoparticles via a calcination process and the capability for photodegradation of diverse contaminants in aqueous solution was explored. Comprehensive morphological, structural, textural, optical, and photoelectrochemical characterization of the prepared samples were executed. The experimental results demonstrated that the as-fabricated heterojunctions can remarkably enhance photocatalytic ability for the degradation of RhB in comparison with the ZnO and ZnBi2O4 components. Furthermore, the optimized ZnO/ZnBi2O4 (10%) sample, with suitable photostability, represented great visible-light-induced photocatalytic efficiency towards the degradation of MB, fuchsine, and MO. The significantly boosted photocatalytic performance was associated with the enhanced visible-light spectral response, inhibited recombination of the charge carriers, and improved textural features, which verified by optical, photoelectrical, electrochemical impedance spectroscopy, and textural measurements. Besides, based on the formed p-n heterojunction between the components, the photocatalytic mechanism was discussed and the conceivable electrons/holes migration and separation pathways were also suggested. (C) 2020 Elsevier B.V. All rights reserved.