Turbulence enhanced ferroelectric-nanocrystal-based photocatalysis in urchin-like TiO2/BaTiO3 microspheres for hydrogen evolution

The application of a built-in electric field due to piezoelectric potential is one of the most efficient approaches for photo-induced charge transport and separation. However, the efficiency of converting mechanical energy to chemical energy is still very low, and the enhancement of photocatalysis, thus, is limited. To overcome this problem, here, we propose sonophotocatalysis based on a new hybrid photocatalyst, which combines ferroelectric nanocrystals (BaTiO3) and dendritic TiO2 to form an urchin-like TiO2/BaTiO3 hybrid photocatalyst. Under periodic ultrasonic excitation, a spontaneous polarization potential of BaTiO3 nanocrystals in response to ultrasonic waves can act as an alternating built-in electric field to separate photoinduced carriers incessantly, which can significantly enhance the photocatalytic activity and cyclic performance of the urchin-like TiO2/BaTiO3 catalyst. More importantly, the significant enhancement of photocatalytic hydrogen evolution is due to the coupling effect of two types of piezoelectric potential in the presence of BaTiO3 nanocubes as well as the semiconductor and optical properties of TiO2 nanowires of the urchin-like TiO2/BaTiO3 hybrid structure under simulated sunlight and periodic ultrasonic irradiation, which can significantly improve the efficiency of converting mechanical energy to chemical energy.

Automated summary

A new hybrid photocatalyst combining ferroelectric nanocrystals and dendritic TiO2 was proposed for sonophotocatalysis, enhancing the photocatalytic activity and cyclic performance by utilizing the spontaneous polarization potential of BaTiO3 nanocrystals under periodic ultrasonic excitation. The significant enhancement of photocatalytic hydrogen evolution was attributed to the coupling effect of two types of piezoelectric potential and the semiconductor and optical properties of the hybrid structure under simulated sunlight and periodic ultrasonic irradiation, leading to improved efficiency of converting mechanical energy to chemical energy.