Enhanced piezo-photocatalytic performance of Cu2O/BaTiO3 p–n heterojunction for efficient dye degradation

Piezo-photocatalysis can effectively combines photocatalysis and piezoelectric polarization to improve the carrier separation efficiency overall performance. Here, Cu₂O/BaTiO₃ p–n heterojunction composite has been successfully synthesized by facile wet chemical method in this work. The synergistic piezo-photocatalytic effect of Cu₂O/BaTiO₃ was investigated for the degradation of dye acid orange 7 (AO7) under simulated solar light illumination and ultrasonic vibration. A significant improvement in dye degradation efficiency was observed, with a remarkable 98.5% degradation achieved within 60 min of piezo-photocatalysis treatment, surpassing the degradation rates observed for individual photocatalysis (53.2%) and piezocatalysis (40.8%). This enhancement can be attributed to the higher spatial separation of photogenerated carriers, facilitated by the heterojunction interface electric field of Cu₂O/BTiO₃ and build-in electric field of BaTiO₃. This unique spatial separation mechanism results in an increased generation of reactive species, ultimately contributing to enhanced degradation of AO7 molecules. This study presents a feasible approach for the synthesis of the Cu₂O/BTiO₃ p–n junction and effectively transcending the limitations inherent to individual Cu₂O or BaTiO₃ in terms of catalytic efficacy.

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