Bi₂WO₆ hierarchical structures have been synthesized by a halide ions-assisted hydrothermal method using Bi(NO₃)₃·5H₂O and Na₂WO₄·2H₂O as the raw materials without any template or surfactant. It is interesting to note that the halide ions (F^‒, Cl^‒ and Br^‒) play a key role on the microstructure of Bi₂WO₆, especially the morphology and surface activity. At the presence of F^‒ in the precursor, the prepared Bi₂WO₆ exhibits a sheet-like morphology with flat surface, and the sheets further intersect with each other to form a three-dimensional structure. However, when Cl^‒ or Br^‒ exist in the precursor, the obtained Bi₂WO₆ with chloride or bromide ions adsorbed on the surface shows a flower-like porous structure constructed by nanosheets, and each nanosheet is assembled by loosely contacted ultrathin nanoplates. The Bi₂WO₆ structures prepared with the assistance of Cl^‒ or Br^‒ behave selectively enhanced adsorption and photodegradation for organic dyes mainly attributed to the active surface and special morphology.

中文翻译：

---

卤离子对罗丹明B增强去除作用对Bi 2 WO 6微观结构的影响

以Bi（NO ₃）₃ ·5H ₂ O和Na ₂ WO ₄ ·2H ₂ O为原料，不用任何模板或表面活性剂，通过卤离子辅助水热法合成了Bi ₂ WO ₆分层结构。有趣的是，卤离子（F ^‒，Cl ^‒和Br ^‒）对Bi ₂ WO ₆的微观结构，尤其是形态和表面活性起着关键作用。在前体中存在F ^‒时，制备的Bi ₂ WO ₆呈现出具有平坦表面的片状形态，并且片进一步彼此相交以形成三维结构。然而，当氯^-或Br ^-存在于所述前体，将所获得的Bi ₂ WO ₆与吸附在表面显示氯化物或溴化物离子的花状每个纳米片由纳米片构成的多孔结构，并通过松散地接触超薄纳米片组装。借助Cl ^‒或Br ^‒制备的Bi ₂ WO ₆结构选择性地增强了对有机染料的吸附和光降解，这主要归因于活性表面和特殊的形貌。