Heterojunction and ferroelectric polarization co-promoting photocatalytic activity

The rapid recombination of photogenerated electrons and holes heavily restricts the photocatalytic efficiency. In this study, a polarized heterojunction photocatalyst g-C3N4/Bi2MoO6 (P-CNBMO) is prepared by high-energy ball-milling process and corona poling post-treatment. In comparison with pristine CN and BMO, all the heterojunctions demonstrate enhanced photocatalytic activity for degradation of tetracycline hydrochloride (TC). After introduction of corona poling, the photocatalytic performance of CNBMO is further increased. The considerably enhanced photocatalytic activity of P-CNBMO is attributed to the collective effect of formation of Type II heterojunction and ferroelectric polarization enhancement, which not only separate the photogenerated electrons and holes between CN and BMO, and also promote the charge separation in the bulk of BMO, as verified by the surface potential from Kelvin probe force microscope (KPFM) and photoelectrochemical measurements. This work is expected to provide referable instructions for the research on the cooperation of heterojunction and ferroelectric polarization for semiconductor photocatalysis.