Photocatalytic degradation of butyl benzyl phthalate by S-scheme Bi/BiOCO/BiS under simulated sunlight irradiation.

As a kind of plasticizer, butyl benzyl phthalate (BBP) presents a serious hazard to the ecosystem. Therefore, there is a strong need for an effective technique to eliminate the risk of BBP. In this work, a new photocatalyst of Bi/BiOCO/BiS with an S-scheme heterojunction was synthesized using Bi(NO) as the Bi source, NaS as the S source, and DMF as the carbon source and reductant. Numerous techniques have been used to characterize Bi/BiOCO/BiS such as scanning electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The improved photoactivity of Bi/BiOCO/BiS was evaluated by photoelectrochemical response, electrochemical impedance spectroscopy, photoluminescence, UV-Vis diffuse reflectance spectroscopy, and electrochemical Mott Schottky spectroscopy. The enhanced photocatalytic activity of this composite for BBP degradation under simulated sunlight irradiation could be attributed to the surface plasmon resonance effect of Bi metal and the heterojunction structure of BiOCO and BiS. The degradation rate of Bi/BiOCO/BiS was 85%, which was 4.52 and 1.52 times that of BiOCO and BiS, respectively. The prepared photocatalyst possessed good stability and reproducibility in eliminating BBP. The improved photocatalytic activity of Bi/BiOCO/BiS was demonstrated with the formation of an S-scheme heterojunction, and the degradation mechanism was discussed with a liquid chromatograph mass spectrometer.