Fabrication of CoFe₂O₄-modified and HNTs-supported g-C₃N₄ heterojunction photocatalysts for enhancing MBT degradation activity under visible light

It is still a challenging work to realize the universality of photocatalytic materials for unselectively removing environmental pollutants in water. Here, a ternary magnetism CoFe₂O₄/g-C₃N₄/HNTs heterojunction photocatalyst is firstly prepared, and the morphology, crystalline property, surface area, and magnetic recycling capability of the photocatalyst were investigated. The CoFe₂O₄/g-C₃N₄/HNTs shows a superior degradation efficiency for degrading 2-mercaptobenzothiazole (MBT) than that of pure g-C₃N₄. The high degradation performance that derives from the hollow structure of halloysite nanotubes (HNTs) can inhibit stacking of g-C₃N₄, which results in a larger specific surface area and more abundant reaction sites. Meanwhile, the heterojunction structure between g-C₃N₄ and CoFe₂O₄ improved the separation efficiency of charge carriers. In addition, the intermediate products, degradation pathway, and reaction mechanism of representative MBT pollutant over the CoFe₂O₄/g-C₃N₄/HNTs photocatalyst are revealed in depth. This work makes an important development.