Dissolved oxygen enhanced piezo-photocatalytic performance in Ag dots-modified BaTiO3 nanoparticles for efficient degradation of multiple organic pollutants

• Published in: Separation and purification technology 2024-10, Vol.346, p.127548, Article 127548
• Main Authors: Gao, Hongcheng, Han, Yi, Wang, Yi, Xia, Hongyu, Zhu, Xiaojing, Wang, Dejin, Zhang, Yuanguang, Mao, Xiaoxia, Zhang, Lijuan
• Format: Article
• Language: English
• Subjects: Ag/BaTiO3; Dissolved oxygen; Dye degradation; Piezo-photocatalytic
• ISSN: 1383-5866
• DOI: 10.1016/j.seppur.2024.127548

Schematic illustration of the piezo-catalytic for the degradation behavior under simulated visible light and ultrasonic activation. [Display omitted] •Ag dots-modified BaTiO3 catalysts with different silver content were successfully prepared.•Ag/BaTiO3 presented good piezo-photocatalytic activity in degrading Rhodamine B under light irradiation and ultrasonic vibration.•The piezo-photocatalytic efficiency of Ag/BaTiO3 was further improved under O2 atmosphere. Piezoelectric nanomaterials have attracted much attention due to their ability to modulate photo-excited carrier separation and migration under strain. Perovskite-structured BaTiO3 (BT) is a promising piezo-photocatalytic material due to its high piezoelectric coefficient and special phase structure. In this work, a series of x wt.% Ag/BT composites prepared by a two-step approach were developed for piezo-photocatalysis applications. The 0.8 wt.% Ag/BT showed an excellent piezo-photocatalytic performance for degrading 75.8 % Rhodamine B (RhB) in 60 min. Especially, the catalytic performances were strongly correlated with the atmosphere conditions of the catalyst. The piezo-photodegradation rate of RhB by 0.8 wt.% Ag/BT under O2 atmosphere reached 95.7 % in 40 min, and the first order kinetic rate constant (k) reached 0.06759 min−1, which was 9.9 and 2.4 times that of N2 and air condition, respectively. The Density functional theory (DFT) calculations further revealed that dissolved oxygen could enhance the material's adsorption of RhB. Compared with hydroxyl free radicals (OH) and holes (h+), superoxide radicals (O2–) play an indispensable role in the catalytic process through the trapping experiments and ESR analyses. Furthermore, the RhB degradation pathway and potential ecotoxicity were also proposed. This work is hoped to provide an understanding the mechanism of piezo-photocatalysis and bring new ideas for the development of piezo-photocatalysis catalysis for multifunctional environmental applications.