Constructing ZIF-67 over S-doped g-C3N4 composites with enhanced photocatalytic degradation performance toward organic pollutants

• ZIF-67/S-doped g-C3N4 (ZIF-67/SCN) heterostructures were assembled. • The ZIF-67/SCN photocatalysts exhibited superior degradation activity under visible light. • Type-II heterojunction mechanism was proposed as appropriate by trapping tests. • High degradation stability was reached by the ZIF-67/SCN photocatalyst. Fabrication and testing of visible-light-motivated hybrid photocatalysts based in sulfur-doped g-C3N4 incorporating Co-zeolitic-imidazolate-framework (ZIF-67) was reported in this research as efficient photocatalysts for visible light-based decomposition of organic dyes. After testing the developed photocatalysts by XRD, FESEM, TEM, EDX, DRS, PL, and EIS techniques, the ZIF-67/S-doped g-C3N4 (30wt%ZIF-67/SCN) sample showed boosted destruction activity (94.6% MB dye degradation efficiency in 60 min) due to the creation of efficient photocatalytic type-II heterojunctions, facilitating the transfer of photogenerated charges. Furthermore, doping g-C3N4 with sulfur effectively increases the response to visible light, thus improving the photocatalyst system's degradation ability. The feasible mechanism of transfer pathways of photocarriers was clarified based on the trapping tests (superoxide radical and holes were the dominate species in the reaction). Moreover, the photostabilities of heterojunctions were verified in this work.