Morphology modulation of hollow-shell ZnSn(OH)6 for enhanced photodegradation of methylene blue

One decisive factor for the photocatalytic performance of ZnSn(OH)6 (ZSO) is nanoparticle morphology. However, the mechanism of the well-defined morphology preparation remains unknown, which leads to the systematic investigation of various parameters in the hydrothermal method. Here, shell-like hollow Archimedean ZSO nanocubes were prepared by a hydrothermal method under suitable conditions, with a uniform particle size distribution and superior dispersion. The effects of hydrothermal time, temperature, pH and surfactant on the microscopic morphology and photocatalytic degradation of methylene blue (MB) dye were investigated. The enhanced photodegradation efficiencies (η) of MB were 97.7%, 96.3%, 89.6%, and 96.2% for 8 h-ZSO, 120 ℃-ZSO, 2.85-ZSO, and Hexadecyl trimethyl ammonium Bromide-ZSO (CTAB-ZSO), respectively, which strongly depended on the morphology, leading to differences in physicochemical properties, such as bandgap and charge transfer resistance. The results suggested that a single change in hydrothermal time, temperature, pH, or surfactant can effectively improve the microscopic morphology and photocatalytic performance of ZSO, which may pave the way for the ingenious design of other high-performance photocatalysts. A growth mechanism was proposed for shell-like hollow ZSO prepared in an alkaline environment.