One-pot hydrothermal synthesis of Bi2O3-WO3 p-n heterojunction film for photoelectrocatalytic degradation of norfloxacin

A p-n heterojunction film of Bi 2 O 3 -WO 3 with enhanced photoelectrocatalytic (PEC) activity was successfully constructed by a facile one-pot hydrothermal synthesis. The as-prepared Bi 2 O 3 -WO 3 heterojunction film exhibited flower-like microstructures. Compared with pristine Bi 2 O 3 and WO 3 films, the Bi 2 O 3 -WO 3 composite film exhibited enhanced absorption in the visible region. The formation of Bi 2 O 3 -WO 3 p-n heterojunction facilitates the interfacial transfer of electrons as well as the separation of charge carries. As a result, the Bi 2 O 3 -WO 3 film showed high photocurrent response under visible light illumination. Furthermore, the enhanced visible light PEC performance of Bi 2 O 3 -WO 3 film was evaluated by the decoloration of Rhodamine B. When the Bi 2 O 3 -WO 3 film was applied to norfloxacin removal, the degradation efficiency reached 88.4% after 6 h PEC process under visible light illumination. According to nine intermediates identified by liquid chromatograph-mass spectrometric analysis, a possible PEC degradation mechanism for norfloxacin was proposed.