Highly efficient harvesting of vibration energy for complex wastewater purification using Bi5Ti3FeO15 with controlled oxygen vacancies

• As-synthesized Bi 5 Ti 3 FeO 15 naturally contains moderate concentration of oxygen vacancies. • Bi 5 Ti 3 FeO 15 is highly active in piezocatalytic degradation of AO7, MO, RhB, MB and their mixture. • Bi 5 Ti 3 FeO 15 shows superior environmental adaptability and stability. • Real textile wastewater can be efficiently degraded by Bi 5 Ti 3 FeO 15 . Piezocatalyst with high and stable efficiency for multiple pollutants degradation shows great promise for practical applications but remains a challenge. Herein, a self-modified oxygen-deficient piezoelectric Bi 5 Ti 3 FeO 15 catalyst is synthesized via a facile method, which demonstrates outstanding piezocatalytic properties. Investigations reveal that an optimal concentration of oxygen vacancies could increase carrier concentration, reduce the electronic impedance and enhance carrier’s separation efficiency under ultrasonic vibration, leading to superior piezocatalytic performance. As a result, the typical pollutants acid orange 7, methyl orange, rhodamine B and methylene blue dyes can be efficiently degraded by 98, 95, 94 and 94%, respectively, within 30 and 50 min (for the latter three dyes), and the acquired degradation efficiencies are higher than most of the previously reported piezocatalysts. Moreover, Bi 5 Ti 3 FeO 15 displayed excellent degradation efficiency for mixed dyes solution with a high first-order rate constant k (0.072 min −1 ), which is higher than most of the reported piezocatalysts for just single dye degradation. In addition, the Bi 5 Ti 3 FeO 15 catalyst possesses superior environmental adaptability and highly efficient degradation ability for real textile wastewater. This work provides a novel and comprehensive strategy for designing high performance oxygen-deficient piezocatalysts that can be further extended to other Bi-based oxides, and also demonstrates that Bi 5 Ti 3 FeO 15 is a promising eco-friendly and superior piezocatalyst for complex wastewater purification by harvesting mechanical energy.