Bi5Ti3FeO15 Nanofibers for Highly Efficient Piezocatalytic Degradation of Mixed Dyes and Antibiotics

A piezocatalyst with highly efficient catalytic efficiency toward multiple pollutants' removal can improve treatment efficiency and reduce the consumption of catalysts, which is ideal for practical applications. Herein, Bi5Ti3FeO15 nanofibers were prepared using electrospinning and its excellent piezocatalytic performances for mixed dyes' and antibiotics' degradation were revealed. Rhodamine B (RhB) is degraded by 98% in 20 min, and the acquired reaction rate constant is 0.195 min–1 under ultrasonic vibration. Particularly, the mixed dyes of RhB, acid orange 7, methylene blue, and methyl orange are simultaneously degraded within 40 min, a high rate constant of 0.106 min–1 is achieved, and the degradation efficiencies can be always maintained at ∼100% for five consecutive cycles. The obtained rate constant for mixed dyes' degradation is superior to many of the previously reported catalysts just toward one dye degradation. Furthermore, it is further demonstrated that tetracycline hydrochloride, bisphenol A, and phenol can be also efficiently degraded by 94, 90, and 79%, respectively, within 30 min. The piezocatalytic performances of nanofibers at different pH values and reaction temperatures were also explored. Catalytic mechanism investigations demonstrate that the optimized Bi5Ti3FeO15 nanofibers possess a weaker carrier recombination rate, smaller carrier transfer resistance, and higher carrier separation efficiency, which account for its superior piezocatalytic performance. This work reveals that Bi5Ti3FeO15 nanofiber is a superior catalyst for organic pollutants' degradation under mechanical vibration and offers a strategy for the design of other high-performance piezocatalysts.