Piezotronic effect boosted photocatalytic performance of heterostructured BaTiO3/TiO2 nanofibers for degradation of organic pollutants

The effective separation of photo-generated electrons and holes is an important factor that determines the photocatalytic efficiency of the catalysts. Here, we propose a core/shell BaTiO3/TiO2 nanocomposites that present enhanced photocatalytic performance through a piezotronic effect. The polarization generated by the piezoelectric phase in the BaTiO3/TiO2 nanofibers prepared by the electrospinning method under ultrasonic activation dramatically improves the photocatalytic performance of the catalysts. Under the co-excitation of ultrasonic and ultraviolet irradiation, the oxidation rate constant of the polarized BaTiO3/TiO2 nanofibers on RhB dye can reach 9.67 × 10−2 min−1, which is 3.51 times and 3.22 times of the corresponding values of TiO2 nanofibers and BaTiO3/TiO2 nanofibers under only UV irradiation, respectively. This paper provides a promising strategy for improving photocatalytic performance through mechanical vibration and helps to understand the coupling mechanism between piezoelectric and photocatalytic effects.