Double activating peroxymonosulfate with g-C3N4/Fe2(MoO4)3 to enhance photocatalytic activity under visible light irradiation

Abstract

Fe₂(MoO₄)₃ photocatalysts were synthesized by a simple hydrothermal method. Fe₂(MoO₄)₃ photocatalysts showed lower photocatalytic activity for the degradation of methylene blue under visible light irradiation. After compositing with g-C₃N₄, the photocatalytic activity of Fe₂(MoO₄)₃ was enhanced obviously. The enhanced photocatalytic activity of the g-C₃N₄/Fe₂(MoO₄)₃ photocatalysts could be attributed to the effective separation of the photogenerated e⁻/h⁺ pairs. In order to further enhance the degradation efficiency of g-C₃N₄/Fe₂(MoO₄)₃, g-C₃N₄/Fe₂(MoO₄)₃ was used to double activate peroxymonosulfate to degrade methylene blue. The influences of peroxymonosulfate dosage, pH value, inorganic anions and methylene blue concentration on double activating peroxymonosulfate to degrade methylene blue were investigated in detail. The mechanism of g-C₃N₄/Fe₂(MoO₄)₃ double activating peroxymonosulfate was proved by radical quenching experiments, which proved that SO₄˙⁻ dominated the degradation of methylene blue.