Photocatalytic and electrochemical characteristics of BiFeO3- TiO2?nanoheterostructure for leather dyes degradation

摘要

The present work was focused on hydrothermal synthesis of the titanium oxide (TiO2) nanorods and bismuth ferrite (BiFeO3)-TiO2 nanoheterostructure on indium tin oxide (ITO) as photocatalysts for photodegradation of leather dyes under visible-light irradiation. The samples were characterized via the SEM, XRD, EIS and UV-Vis absorption spectra. SEM results revealed that high density and high aspect ratio of BiFeO3-TiO2were successfully grown on ITO substrate. XRD analysis exhibits that both the TiO2 and BiFeO3 phases coexist, which shows that there aren’t any impurity phases at the interface between BiFeO3 and TiO2 with the synthesis condition. Optical characterization results revealed that BiFeO3 nanoparticles leads to reduction the band-gap of TiO2 nanorods which were calculated to be 2.93 and 2.58 eV for the TiO2 and BiFeO3/TiO2nanoheterostructure, respectively. EIS analysis shows that BiFeO3/TiO2 revealed lower recombination rate of electron-hole pairs which accelerate the photocatalytic reactions. The degradation efficiency for BiFeO3/TiO2 nanoheterostructure was 88% after 90 min under visible-light radiation which was significantly greater than its degradation efficiency (54%) in TiO2 nanorods. These findings exhibited that the BiFeO3/TiO2 has the excellent visible-light harvesting performance for degradation of leather dyes.