Efficient -scheme charge separation in WO/PbWO for the removal of organic pollutants

The contact quality of a composite is an important factor for the transfer and separation of photogenerated carriers. For this, we demonstrated a cation exchange method for the in situ construction of WO 3 /PbWO 4 linked by WO 6 octahedral crystal structure units, where WO 3 was placed on the surface of PbWO 4 . We found that the apparent rate constant of the as-prepared WO 3 /PbWO 4 was significantly increased (17 times higher than any single one). Our investigation indicated a remarkably enhanced photodegradation rate, originating from high contact quality. The photogenerated carriers of WO 3 /PbWO 4 were greatly separated via the grain boundary, making WO 3 /PbWO 4 exhibit 22 times higher photocurrent density than pristine PbWO 4 . Moreover, the photoelectrons and holes were separated through the high contact quality grain boundary built-in electric field, which is in accordance with the transmission path of the Z -scheme. Compared with the interface, a grain boundary is more conducive to the photocatalytic process. This study provides a feasible strategy to build a highly efficient Z -scheme photocatalyst with high contact quality grain boundary to remove organic pollutants. The contact quality of a composite is an important factor for the transfer and separation of photogenerated carriers.