O x ygen Vacancy‐Enhanced Centrosymmetric Breaking of SrFeO 3‐ x for Piezoelectric‐Catalyzed Synthesis of H 2 O 2

Abstract Normally, only noncentrosymmetric structure of the materials can potentially be piezoelectric. Thus, it is limited in the field of piezoelectricity for the centrosymmetric structure of the material. In this work, the performance of piezoelectricity is successfully achieved from centrosymmetric SrFeO 3‐ x by modulating o x ygen vacancies, which have a surface piezoelectric potential up to 93 mV by using Kelvin‐probe force microscopy (KPFM). Moreover, the piezoelectric effects of SrFeO 3‐ x are also evaluated by piezoelectric catalytic effect and density functional theory calculations (DFT). The results show that the piezo‐catalytic degradation of tetracycline reaches 96% after 75 min by ultrasonic mechanical vibration and the production of H 2 O 2 by SrFeO 3‐ x piezoelectric synthesis could reach 1821 µmol L −1 . In addition, the DFT results indicate that the intrinsic effect of o x ygen vacancies effectively promotes the adsorption and activation of O 2 and H 2 O as well as intermediates and improves the piezoelectric catalytic activity. This work provides an effective basis for realizing the piezoelectricity of centrosymmetric materials and regulating the development of piezoelectric catalytic properties.