Strong synergy of piezoelectric photocatalysis in PFC catalyzed by BaTiO3/Bi2WO6 anode and with peroxymonosulfate to remove rhodamine B

In this study, BaTiO3/Bi2WO6 was prepared via a facile hydrothermal method and tested as the anode catalyst in piezo-photocatalytic fuel cells (PZ-PFC) degrading rhodamine B (RhB). The optimal composite catalyst H11 has a molar ratio of 1:1 for BaTiO3 to Bi2WO6. It was characterized using TEM, XPS and UV–Vis etc. Its performance in PFC on stainless-steel anode (counter carbon rod cathode) and the reaction rate constant in RhB removal is 7.13 times the BaTiO3 anode and 5.26 times the Bi2WO6 anode. The reaction rate constant using H11 in PZ-PFC was 0.08 min −1 with visible light irradiation and constant aeration, it was 115 times the PFC without aeration and 3.15 times the PZ-FC without photocatalysis, indicating the strong synergy of photocatalysis with piezoelectric catalysis in PZ-PFC. With only 0.07 mM peroxymonosulfate (PMS), forming the PMS-PZ-PFC, the kinetic reaction rate constant (K) was 0.14 min−1, 1.66 times the PZ-PFC system. Singlet oxygen and hydroxy radicals played more significant role in degrading pollutant in such process. With micro/nano bubble in the PMS-PZ-PFC, the reaction rate constant was higher than without micro/nano bubble. The PMS-PZ-PFC synergy system has high application potential in water treatment. Graphical abstract