Facile fabrication of well-polarized Bi2WO6 nanosheets with enhanced visible-light photocatalytic activity

A universal and facile strategy is proposed to fabricate polarized Bi2WO6 nanoparticles with the assistance of a soluble organic-inorganic composite film. After electric poling, there is no significant change in the crystal structure or morphology as confirmed by XRD, SEM and TEM studies. By combining piezoresponse force microscopy (PFM), photoinduced silver deposition and time-resolved photoluminescence (PL) testing, it can be revealed that the promoted separation and prolonged lifetime of photogenerated carriers are unambiguously caused by ferroelectric polarization. The visible-light-driven photocatalytic activity of the polarized Bi2WO6 nanosheets was significantly improved by 2-fold compared to that of pristine Bi2WO6. This electric poling strategy offers a new route for large-scale fabrication of various polarized ferroelectric nanoparticles, and has immense potential for practical applications in catalysis, optoelectronics and energy storage devices.