Designing 3D magnetic peony flower-like cobalt oxides/g-C3N4 dual Z-scheme photocatalyst for remarkably enhanced sunlight driven photocatalytic redox activity

In this study, a novel 3D magnetic Co 3 O 4 @CoO/g-C 3 N 4 ternary hybrid possessing double Z-scheme mechanism has been designed and architected by wet-impregnation and subsequent controlled oxidation process . In the Co 3 O 4 @CoO/g-C 3 N 4 ternary hybrid system, g-C 3 N 4 ultrathin nanopieces uniformly dispersed on each nanopetal of peony flower cobalt oxides , which not only helps to enhance the light absorption efficiency and avoid the aggregation but also readily promote the separation of photo-induced charge. Benefiting from the special hierarchical architecture, large open space between nanopetals and the synergistic effect between cobalt oxides and g-C 3 N 4 , when employed as photocatalyst for reduction of nitrobenzene (NB) and degradation of tetracycline (TC), 3D Co 3 O 4 @CoO/g-C 3 N 4 exhibited superior redox reactivity. Notably, a double Z-scheme heterojunctions and well matched band structures could further facilitate effective charge transfer. Meanwhile, Co 3 O 4 @CoO/g-C 3 N 4 ternary hybrids also exhibited excellent magnetic separation property and super cycling stability after four cycles, which make it a promising candidate as a visible light photocatalyst for practical application.