Polyethylene glycol (PEG)-modified Ag/Ag2O/Ag3PO4/Bi2WO6 photocatalyst film with enhanced efficiency and stability under solar light

Abstract Bi2WO6 photocatalyst possesses great photocatalytic properties, modification with Ag, Ag2O, and Ag3PO4 further improve its photocatalytic activity. Photocatalyst utilized as suspended powders in wastewater treatment imposes restrictions for practical application. Therefore, the design and fabrication of photocatalyst film with high efficiency and stability are crucial for practical application. In this study, polyethylene glycol (PEG) modified AP-BWO (A: Ag, Ag2O; P: Ag3PO4; BWO: Bi2WO6) photocatalyst film coated on glass substrate was firstly synthesized with excellent photocatalytic activity and stability. Bi2WO6based films were modified with different PEG molecular weight, dosage and coating layers, followed by characteristic analysis (SEM, TEM, XPS, UVvis, PL, and photocurrent density) and photodegradation test. Photodegradation showed that 2-layered of 12 g L−1 PEG2000 modified AP-BWO film exhibited the highest photocatalytic activity. XPS and TEM indicated that PEG2000-AP-BWO film was fabricated successfully. SEM and UV–vis denoted the photocatalyst film showed small particle size and strong visible-light absorption. Furthermore, PL and photocurrent density confirmed its low recombination and fast charge separation of electronhole pairs. The photocatalytic films showed high activity and stability in both 10-cycle repeatability experiments and tandem-type photocatalytic recycle system. Therefore, PEG2000-AP-BWO film with enhanced photocatalytic performance and stability was a promising alternative for wastewater treatment.