Photo-Fenton-like degradation of Rhodamine B dye from waste water using iron molybdate catalyst under visible light irradiation

Abstract

Iron molybdate Fe2(MoO4)3 nanopowders with different morphologies have been successfully tailored using two different techniques; co-precipitation and sol gel auto-combustion methods Evidently, X-ray diffraction (XRD) profiles manifested that monoclinic Fe2(MoO4)3 with space group P21/a was acquired at different annealing temperatures from 400 to 600°C for 2h using both routes. FE-SEM micrographs evidenced that the formed particles was exhibited aggregates of plates staked with different directions for the sample annealed at 400°C which it was converted to the brain or an array of fused spheres for the samples annealed at 600°C using co-precipitation strategy. Otherwise, the microstructure of the formed particles was appeared as a homogeneous porous spherical cluster for Fe2(MoO4)3 sample annealed at 400°C which it was showed a honey comb like for the sample annealed at 600°C. Overall, Fe2(MoO4)3 nanopowder prepared by co-precipitation method at 400°C was exhibited the highest photo Fenton catalytic activity with efficiency ∼97% for degradation of RhB dye after 60min. In this regards, the highest catalytic activity was attributed to the strong absorption of Fe2(MoO4)3 in the visible-light region due to high surface area of the distinct morphologies and generation of reactive OH from H2O2 synergistically activated by both Fe3+ and MoO42−.