Synergistic mediation of metallic bismuth and oxygen vacancy in Bi/Bi2WO6-x to promote 1O2 production for the photodegradation of bisphenol A and its analogues in water matrix

Bi/Bi2WO6-x heterostructures has been successfully prepared by a facile one-step hydrothermal method. By maneuvering reaction time and Bi/W molar ratio of the precursors, we have been able to selectively introduce oxygen vacancy and metallic Bi into Bi2WO6 nanostructures. The obtained Bi/Bi2WO6-x heterostructures with more oxygen vacancy and moderate metallic Bi exhibit significantly improved photocatalytic activity for the photodegradation of bisphenol A (BPA) and its analogues due to its great ability for the generation of singlet oxygen (1O2), which has proven to work as the main reactive oxygen species during photocatalysis. It is also found the 1O2 concentration is highly depended on and modulated by the content of oxygen vacancy and metallic bismuth. Besides, we also demonstrate that the obtained Bi/Bi2WO6-x products display efficient photocatalytic performance toward BPA derivatives degradation and enhanced stability to resist the interferences in the water matrix.