Synergistic polarization and oxygen vacancies engineering for enhancing photocatalytic NO removal over Bi4Ti3O12 nanowires

Enhanced polarization emerges as a potent strategy for further enhancing the photocatalytic performance of a photocatalyst. Considering the anisotropy of ferroelectric polarization and the improvement of polarization by defects, [010] preferred growth Bi4Ti3O12 nanowires with oxygen vacancies were prepared via a hydrothermal method. Bi4Ti3O12 nanowires exhibited a photocatalytic NO removal efficiency of up to 67.5% under visible light irradiation (λ > 420 nm), which is much higher than that of its counterpart, Bi4Ti3O12 (3%). Structural characterizations and theoretical calculations support that, the engineering of oxygen vacancies in Bi4Ti3O12 can enhance the polarization in the [010] and [100] directions, and gradually shifted the polarization dominant direction of Bi4Ti3O12 from [100] to [010]. Overall, the improved polarization and generated oxygen vacancies enhanced the photocatalytic NO removal performance of Bi4Ti3O12 nanowires. This work elucidates the significance of rational engineering oxygen vacancy-based microstructures and utilizing the polarization to amplify the photocatalytic performance.