Synthesis of Z-type spherical B-g-C3N4/Bi2WO6 heterojunctions for enhanced rhodamine B degradation

A spherical B-g-C3N4/Bi2WO6 heterojunction photocatalyst was synthesized using the hydrothermal coprecipitation method. Scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and ultraviolet–visible diffuse reflectance spectroscopy (DRS) showed that B-g-C3N4 was uniformly dispersed on the Bi2WO6 surface through a strong chemical bond, reducing the energy bandgap of Bi2WO6. The outcomes of the experiment regarding the photocatalytic degradation of rhodamine B (RhB) demonstrated a notable enhancement in the degradation rate for the 1:3 BCN/BWO composite. Specifically, the degradation rate was found to be 76 times greater than that of B-g-C3N4 and 7 times higher than that of Bi2WO6. Furthermore, a photocatalytic degradation mechanism was proposed based on the results of ultraviolet photoelectron spectroscopy (UPS) and free radical capture experiments. The direct Z-type B-g-C3N4/Bi2WO6 heterojunction structure promotes the effective separation of photogenerated carriers and enhances their oxidation-reduction ability.