Synthesis of Z-scheme g-C3N4/PPy/Bi2WO6 composite with enhanced visible-light photocatalytic performance

An all-solid-state Z-scheme photocatalytic system g-C3N4/PPy/Bi2WO6 (GPB) is successfully fabricated by introducing both polypyrrole (PPy) and graphitic carbon nitride (g-C3N4) nanoparticles on the surface of Bi2WO6 microflowers. PPy, as a kind of conductive polymers, can be regarded as the Ohmic contact in Z-scheme systems. Furthermore, PPy serves as a charge transmission bridge between the g-C3N4 and the Bi2WO6. The g-C3N4/PPy/Bi2WO6 sample with the PPy amount of 0.5 wt% (GPB-0.5) exhibits enhanced visible-light absorption and high electron-hole separation efficiency. It can remove 98.0% of RhB within 100 min, the photocatalytic activity of which is higher than that of other control samples. Both photoelectrochemical test and scavenging experiment identify that h(+) and center dot O-2(-) are the main active species in the photocatalysis process. Our work could offer a new sight to design and fabricate photocatalyst with excellent utilization efficiency of solar energy.