Enhanced photo-Fenton degradation of fluoroquinolones in water assisted by a 3D composite sponge complexed with a S-scheme MoS2/Bi2S3/BiVO4 ternary photocatalyst

A constructed MoS2/Bi2S3/BiVO4 ternary photocatalyst(MBB) mainly with a S-scheme heterostructure was loaded on a 3D lignosulfonate modified poly(vinyl formal) sponge to obtain a novel composite sponge(PLS-MBB) with an enhanced performance in synergistic adsorption and photo-Fenton degradation of various fluoroquinolones(FQs) in water. The synergistic adsorption and photocatalysis of PLS-MBB notably improved the applicable pH from 2.0 to 9.0 and reduced the dosage of Fe2+ to 0.014 mmol/L in Fenton reaction, which could achieve the degradation efficiency of 92.8 % for FQs within 60.0 min at pH 6.0. The photo-generated electrons by MBB and the redox transformation of Mo(IV)/Mo(VI) and Bi(III)/Bi(V) accelerated the conversion of Fe3+ to Fe2+; besides, the efficient adsorption of FQs on the sponge carrier promoted the surface degradation in solution, thereby causing an enhanced photo-Fenton reaction. This work provided a novel strategy to improve photo-Fenton reaction and accordingly fabricated a talented material for effective removal of organic contaminants in water.