One-step synthesis of unique thorn-like BaTiO3–TiO2 composite nanofibers to enhance piezo-photocatalysis performance

Abstract Piezo-photocatalysis materials that can effectively utilize mechanical energy of water flow have become one of the research focuses in the field of water pollutant treatment. Herein, the unique thorn-like BaTiO3–TiO2 composite nanofibers were prepared in one step by coaxial electrospinning. The surface TiO2 nanorods and the core BaTiO3 nanofiber presented a certain angle when the advancing speed ratio of the shell and core solution was 2:1. The TiO2 nanorods were tightly bonded to the nanofiber and the thorn-like protrusions on the fiber surface were sensitive to water flow. The BaTiO3–TiO2 composite nanofibers exhibited excellent photocatalytic performance and recyclability with the bandgap value of 3.12 eV. The photocatalytic degradation rate of BaTiO3–TiO2 composite nanofibers was 99.8% under the vibration of tiny water current, while the degradation rate was just 56.1% without vibration. Scavenger study result indicated that superoxide radicals and hydroxyl radicals were the main factors to improve the photodegradation activity of the samples. After five cycles, the degradation rate still reached 98.6%. The obtained thorn-like BaTiO3–TiO2 composite nanofibers can effectively utilize the tiny water vibration energy and have broad application prospects in the field of water treatment. Most importantly, the method of synthesizing a unique thorn-like structure is universal.