A g-C3N4/Mn3O4/ZIF-8 composite for efficient degradation of dyes by activating peroxymonosulfate

The photocatalytic degradation of dyes by graphitic carbon nitrides (g-C 3 N 4 ) under sunlight has received increased attention. However, the fast recombination of charge carriers still restricts its photocatalytic application. To overcome this drawback, a g-C 3 N 4 /Mn 3 O 4 /ZIF-8 (CMZ) composite was prepared to activate peroxymonosulfate (PMS)-based advanced oxidation processes for degradation of rhodamine B (RhB) in water. Under visible light , the catalysts exhibited high activity and stability in activating PMS to generate radicals ( · OH, · O 2 − and SO 4 · - ) and the maximum RhB degradation of approximately 94.34 % was achieved. The RhB degradation followed first‐order kinetics and the rate constant of g-C 3 N 4 /Mn 3 O 4 /ZIF-8/PMS system was 2.85, 3.09, 9.82 and 17 times of g-C 3 N 4 , Mn 3 O 4 , ZIF-8 and PMS, respectively. Moreover, the synergistic effect of CMZ and PMS on the removal efficiencies of total organic carbon (TOC) for RhB and wastewater were 92.84 % and 96.13 %, respectively. After five cycles of use, the degradation rate of the prepared catalyst for RhB only decreased by 1.7 %. This work provided new insights that the synergistic effect of advanced oxidation technologies and photocatalysis holds broad prospects for the photodegradation of RhB.