In situ facile fabrication of Z-scheme leaf-like beta-Bi2O3/g-C3N4 nanosheets composites with enhanced visible light photoactivity

In this work, leaf-like beta-Bi2O3/g-C3N4 nanosheets composites were synthesized via a simple in situ method. beta-Bi2O3/g-C3N4 nanocomposites were obtained via calcining the mixtures of g-C3N4 and metallic Bi, while, at the same temperature, in the absence of g-C3N4, metallic Bi formed alpha-Bi2O3. The presence of beta-Bi2O3 in the composite was demonstrated by X-ray diffraction, high-resolution transmission electron microscopy (HRTEM) and X-ray photoelectron spectroscopy analysis. From scanning electron microscope analysis, the morphology of leaf-like beta-Bi2O3 and the g-C3N4 nanosheets were observed. The as-prepared beta-Bi2O3/g-C3N4 composite exhibited higher photocatalytic activity than both pure beta-Bi2O3 and g-C3N4 for photocatalytic degradation of methylene blue under visible light. The active species capture experiments and photoluminescence experiments illustrated that the degradation mechanism followed the Z-scheme mechanism. This proposed method provides an efficiency way to prepare potential visible light responsive materials for wastewater treatment.