Accessible fabrication and mechanism insight of heterostructured BiOCl/Bi₂MoO₆/g-C₃N₄ nanocomposites with efficient photosensitized activity

Semiconductor nanostructures perform wide applications in light-driven physical and chemical processes; the photophysical and chemical properties of semiconductors can be adjusted by changing their shape, size and composition. To investigate the effect of g-C₃N₄ loadings on the nonlinear optical and photocatalytic performances, a series of novel BiOCl/Bi₂MoO₆/g-C₃N₄ nanocomposites loaded with different g-C₃N₄ contents was prepared via a facile refluxing process. The existence of strong interfacial interactions between BiOCl/Bi₂MoO₆ and g-C₃N₄ was confirmed by a series of characterization techniques including X-ray photoelectron spectroscopy and UV-vis diffuse reflectance spectroscopy. The electrochemical impedance spectroscopy, photoluminescence and nanosecond time-resolved emission confirmed that the interface charge separation efficiency of BiOCl/Bi₂MoO₆/0.10C₃N₄ was greatly improved, resulting in a higher activity toward photodegradation of Rhodamine B and a higher photocurrent density. The associated photocatalytic activity of BiOCl/Bi₂MoO₆/g-C₃N₄ nanocomposites is shown to be dependent on the g-C₃N₄ loadings. An improved nonlinear optical performance was also observed for BiOCl/Bi₂MoO₆/0.10C₃N₄ nanocomposite. These results reveal the photosensitized mechanisms of BiOCl/Bi₂MoO₆/g-C₃N₄, and demonstrate their practical use as recyclable photocatalyst and optical limiters. This method may usher a new phase for the preparation of novel and highly efficient ternary heterostructures for energy conversion, light harvesting and optical limiting applications. - Highlights: • A series of novel BiOCl/Bi₂MoO₆/g-C₃N₄ nanocomposites was prepared. • Optical studies reveal the broadband light absorptivity of the nanocomposites. • Superior photocatalytic efficiency was observed for the nanocomposites. • The samples exhibited dual functionality as photocatalysts and optical limiters.