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

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.