Enhanced photocatalytic properties of α-SnWO₄ nanosheets modified by Ag nanoparticles

Decoration of silver nanoparticles (Ag-NPs) on surface of α-SnWO₄ nanosheets has been achieved by a microwave-assisted deposition method. The as-synthesized products are structurally characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The results illustrate that Ag-NPs are evenly anchored onto α-SnWO₄ surface to form close heterojunction and the amount of Ag nanoparticles grown on α-SnWO₄ nanosheets can be well controlled by tuning Ag⁺ concentration. The photocatalytic properties of Ag-NPs/α-SnWO₄ composites are evaluated by degrading methyl orange (MO) under visible-light irradiation. Ag-NPs/α-SnWO₄ composites exhibit better photocatalytic properties than that of pure α-SnWO₄, and Ag-NPs/α-SnWO₄ (5mol% Ag) presents the best photocatalytic activity, whose photodegradation efficiency of MO is about 97% within 70min. In addition, the obtained samples demonstrate good recyclability. The enhanced photocatalytic properties was attributed to synergistic effect between Ag-NPs and α-SnWO₄ nanosheets, which can increase absorption of visible light enabled by surface plasma resonance (SPR) of Ag-NPs and facilitate the separation of photogenerated electron-hole pairs.