Solvent-free mechanochemical synthesis of well-dispersed single crystalline zinc hydroxystannate and their photocatalytic properties

Single crystalline zinc hydroxystannate (ZHS) cubes in submicron scale were prepared by a facile grinding method without any use of solvent. The X-ray diffraction and selected area electron diffraction indicate the well crystalline cubic perovskite structure of the as-prepared sample. The scanning electron microscopy and transmission electron microscopy show that the cubic morphology of ZHS crystal is well dispersed with narrow size distribution. The ZHS cubes can be formed in a short time through chemical reaction activated by mechanical power. The grinding time and molar ratio of reagents can effectively change the size and morphology of the ZHS crystals. The formation mechanism of ZHS cubes was proposed based on the attachment growth model. The photocatalytic activity of ZHS cubes for deconstruction of nitrogen monoxides (NO) gas was evaluated, which showed comparable photocatalytic activity to that of commercial titania (P25).