Mei Su,Yulu Chen,Linqi Wang,Zihao Zhao,Honggang Sun,Guoli Zhou,Pan Li
In our study, a series of WO 3 /Bi 2 MoO 6 heterostructured photocatalysts consisting of Bi 2 MoO 6 nanosheets and WO 3 nanorods were synthesized. Due to the Bi 2 MoO 6 nanosheets with two-dimensional structure, the as-prepared WO 3 /Bi 2 MoO 6 heterostructures had abundant oxygen vacancy defects and high exposure of active Bi 2 MoO 6 (010) facets. Compared with the pure Bi 2 MoO 6 and the oxygen vacancy-poor WO 3 /Bi 2 MoO 6 sample, the WO 3 /Bi 2 MoO 6 heterostructure with WO 3 weight ratios of 6 wt% (denoted as WO/BMO(6)) displayed improved photocatalytic activities in degradation of RhB and OTC under visible-light irradiation. The photoluminescence spectra, photoelectrochemical measurements and DOS analysis illustrated that the desirable photocatalytic performance of the WO/BMO(6) composite was attributed to the synergistic effect of heterojunction interface and oxygen vacancy defects on the efficient charge separation and transfer. Based on the trapping experiments, a Z-scheme charge transfer mechanism was proposed for the WO 3 /Bi 2 MoO 6 heterostructure.
Liruhua Zhang,Zhixiang Chen,Yi Lu,Qingxia Liu,Lingbing Kong
The synergy between surface oxygen vacancies (OVs) and heterojunction engineering holds promising potential for substantially enhancing photoelectric conversion efficiency through the optimization of photogenerated charge carrier transport. Herein, novel WO 3 -OVs@Bi 2 MoO 6 S-scheme heterostructures are synthesized via a simple route for degradation of tetracycline hydrochloride (TC) using visible light. The S-scheme charge transfer mode markedly enhances the spatial separation and preservation of high-energy electrons/holes on Bi 2 MoO 6 (reduction) and WO 3 -OVs (oxidation), consequently providing WO 3 -OVs@Bi 2 MoO 6 photocatalysts with an improved redox capability. The optimal WO 3 -OVs@Bi 2 MoO 6 heterojunction demonstrates enhanced visible-light-driven photocatalytic degradation of tetracycline, exhibiting 4.86-fold and 4.17-fold higher efficiency compared to WO 3 -OVs and Bi 2 MoO 6 , respectively, with superior stability and reusability. Confirmation of the existence of the S-scheme charge transfer mechanism and oxygen vacancies (OVs) is achieved through a combination of density functional theory (DFT) calculations and in-situ X-ray photoelectron spectroscopy (XPS), substantiating the enhancement of charge separation and redox capability. Specifically, the presence of oxygen vacancies (OVs) on the surface of WO 3 nanofibers results in a reduction of the band gap energy due to the defect levels, consequently promoting increased electron conduction. Furthermore, the abundance of oxygen vacancies (OVs) expands the photo response range and facilitates charge transfer at the interface. This research opens new avenues for the successful photocatalytic degradation of tetracycline (TC) by integrating hierarchical S-scheme heterojunction design and cutting-edge defect engineering in photocatalytic heterojunctions.
危险品化学品经营许可证（带存储）