Z-Scheme g-C3N4/Fe3O4/Ag3PO4 @Sep magnetic nanocomposites as heterojunction photocatalysts for green malachite degradation and dynamic molecular studies

In this study, we successfully prepared a Z-scheme heterostructures’ nanocomposite using a co-precipitation method. The nanocomposite was characterized using several techniques, and the results showed that the surface of sepiolite was occupied by Fe3O4, Ag3PO4, and g-C3N4 nanoparticles. The photocatalytic performance of the g-C3N4/Fe3O4/Ag3PO4 @Sep nanocomposite was found to be significantly better than that of pure g-C3N4, g-C3N4 @Sep, and g-C3N4/Ag3PO4 @Sep. The enhancement in photocatalytic activity was attributed to the synergistic effects of the Z-scheme heterojunction construction, which improved light usage and charge carrier migration rate. The nanocomposite also exhibited good stability and reusability even after four cycles, as it was confirmed by MD calculations. Additionally, the DFT-D correction was used to optimize all the structures, and the MG adsorption was investigated using the adsorption locator module, suggesting the thermodynamic stability of the system. Overall, this study provides important insights into the design and synthesis of Z-scheme nanocomposite heterojunctions for efficient photocatalytic applications. [Display omitted] •A one-step coprecipitation method was used to synthesize the photocatalyst Z-scheme g-C3N4/Fe3O4/Ag3PO4 @Sep magnetic nanocomposite.•The photocatalytic efficiency of the g-C3N4/Fe3O4/Ag3PO4 @Sep nanocomposite was significantly improved for the degradation of MG dye as compared to individual g-C3N4 and Ag3PO4.•The g-C3N4/Fe3O4/Ag3PO4 @Sep nanocomposite exhibited efficient visible-light-driven photo-degradation activity and stability.•DFT calculations were used to investigate the MG adsorption in the g-C3N4/Fe3O4/Ag3PO4 @Sep.