Preparation of phosphorus-doped tungsten trioxide nanomaterials and their photocatalytic performances

In this study, a highly efficient and stable phosphorus-doped Tungsten trioxide (P-WO3) photocatalyst was successfully synthesized using a combination of hydrothermal and post-calcination method. The microstructures, morphologies and optical properties of the obtained WO3 and P-WO3 samples were characterized. The results showed that P was uniformly doped into the WO3 lattice in a pentavalent-oxidation state (P5+). The charge carrier traps were also formed, which could accept the photoelectrons. Furthermore, the band gap energy was reduced from 2.4 to 2.33 ev. The photocatalytic performance of the obtained P-WO3 samples with different P concentrations were then tested by photocatalytic degradation of methyl blue (MB). It was found that the 6%-P-WO3 sample exhibited the highest photocatalytic activity, with 96% of MB being able to be degraded within 120 min, which was more than four times higher than that of the pure WO3. The practicality of the prepared P-WO3 was also evaluated using samples from two domestic wastewater treatment plants. The P-WO3 had a high photodegradation performance in treating low concentration of organic matters from real wastewater. The photocatalysis of P-WO3 could be mainly initiated by the production of hydroxyl radical (·OH) and photogenerated hole (h+).