Self-assemble flower-like SnO₂/Ag heterostructures: Correlation among composition, structure and photocatalytic activity

Three-dimensional flower-like SnO₂/Ag heterostructures were self-assembled via a simple microwave hydrothermal treatment of a mixture of tin (II) dichloride dihydrate (SnCl₂·2H₂O), sodium citrate (Na₃C₆H₅O₇·2H₂O) and silver nitrate (AgNO₃) in an alkali solution. The morphological, structural and optical properties of the heterostructures were investigated by means of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), photoluminescence spectra (PL) and Raman spectra, and a detailed formation mechanism was discussed. The photocatalytic activities of the samples were evaluated by degradation of rhodamine B (RhB) in an aqueous solution under ultraviolet light irradiation. Morphology and photocatalytic activity of the SnO₂/Ag heterostructures were tailored as the addition amount of Ag. SnO₂/Ag heterostructures with 3% content of Ag showed best photocatalytic performance.