Novel Bi2O2CO3/polypyrrole/g-C3N4 nanocomposites with efficient photocatalytic and nonlinear optical properties

Semiconductor nanostructures perform wide applications in light-driven physical and chemical processes; in particular, nanomaterials based on Bi2O2CO3 with tunable photophysical properties have attracted intense interest. However, the nonlinear optical properties and photocatalytic performances of the ternary system Bi2O2CO3/polypyrrole/g-C3N4 have not been reported. In this paper, a series of novel Bi2O2CO3/polypyrrole/g-C3N4 nanocomposites loaded with different g-C3N4 contents was prepared to maximize the photocatalytic activity and optical nonlinearity. The structure, composition and morphology of the as-prepared samples were characterized by Fourier-transform infrared spectroscopy, X-ray powder diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy and Raman spectroscopy. The wide absorption of the samples in the visible light region makes them suitable for photocatalytic and nonlinear transmission studies. Their photocatalytic performances were evaluated by degradation of rhodamine B. The associated photocatalytic activity of Bi2O2CO3/polypyrrole/g-C3N4 nanocomposites is shown to be dependent on the g-C3N4 loading. Compared to Bi2O2CO3, PPy, g-C3N4, BP and B/C0.5, the BP/C0.5 composite with 0.5 wt% g-C3N4 exhibits the highest photocatalytic activity. The nonlinear optical properties were investigated by open-aperture Z-scan measurements at 532 nm with 4 ns laser pulses. The results demonstrated that the BP/C0.5 composite exhibited improved properties for photocatalysis and optical nonlinearity, which is ascribed to a combination of mechanisms.