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

Abstract

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.