High-efficiency and mechano-/photo- bi-catalysis of piezoelectric-ZnO@ photoelectric-TiO2 core-shell nanofibers for dye decomposition

Abstract

A mechano-/photo- bi-catalyst of piezoelectric-ZnO@photoelectric-TiO₂ core-shell nanofibers was hydrothermally synthesized for Methyl Orange (10 mg L^-1) decomposition. The mechano-/photo- bi-catalysis in ZnO@TiO₂ is superior to mechano- or photo-catalysis in decomposing Methyl Orange, which is mainly attributed to the synergy effect of the piezoelectric-ZnO core's mechano-catalysis and the thin photoelectric TiO₂ shell's photo-catalysis. The heterostructure of the piezoelectric-ZnO@photoelectric-TiO₂ core-shell interface, being helpful to reduce electron-hole pair recombination and to separate the piezoelectrically-/photoelectric ally- induced electrons and holes, may also make a great contribution to the enhanced catalysis performance. The mechano-/photo-bi-catalysis in ZnO@TiO₂ core-shell nanofibers possesses the advantages of high efficiency, non-toxicity and tractability and is potential in utilizing mechanical/solar energy to deal with dye wastewater.

Keywords: Core-shell; Dye decomposition; Mechano-catalysis; Photo-catalysis; Piezoelectric effect; ZnO@TiO(2).