High photocatalytic activity of magnetic composite photocatalyst NIFe₂O₄/BiVO₄ for rhodamine B degradation under visible led light Irradiation

Abstract

To improve the photocatalytic activity of BiVO₄ semiconductor, the design of composite photocatalyst containing BiVO₄ with surpassing the recombination of photoinduced electron and hole is highly required. In this study, magnetic composite photocatalyst with NiFe₂O₄ and BiVO₄ has developed through two-steps hydrothermal method. The results show that the morphology of the bare BiVO₄ had a decahedral shape with smooth surfaces along with particles, while the morphology of the bare NiFe₂O₄ had nanoparticles with the diameter in a range of 10-20 nm. In the case of 20 % NiFe₂O₄/BiVO₄ samples, a lot of nanoparticles were deposited into large bulk, implying the incorporation of NiFe₂O₄ nanoparticlcs on the surface of BiVO₄ catalyst. Compared with the bare BiVO₄, the NiFe₂O₄/BiVO₄ composites had a higher photocatalytic efficiency for photodecomposition of rhodamine B (RhB) under visible LED light irradiation. The improvement of photocatalytic degradation RhB activity should be attributed to a direct Z-scheme system. Therefore, the fabrication of semiconductors with a combination of magnetic materials provides new insight for the enhancement of their photocatalytic performance.