Facile synthesis of core–shell structured ZrO2@SiO2 via a modified Stöber method

Abtract Here, a simple and reproducible method for the preparation of a well-defined zirconia@silica core–shell nanostructure is described. We studied the morphology, size, and composition of prepared nanoparticles (NPs) by transmission electron microscopy , scanning electron microscopy, dynamic light scattering, Fourier transform infrared spectroscopy , X-ray diffraction, and energy-dispersive spectroscopy. ZrO 2 NPs were synthesized through a novel alcohol–water mixed system using ZrOCl 2 ·8H 2 O as the zirconium source under mild hydrothermal conditions (110–120   °C). These NPs were then used as the core for the deposition of a silica shell via a modified Stöber method, resulting in uniform core–shell ZrO 2 @SiO 2 composites with a tunable silica shell thickness and controllable core morphology. In addition, the effect of the agent polyvinylpyrrolidone (PVP) on the formation of the core–shell structure was investigated in detail. The results demonstrated the PVP played a critical role in stabilizing the NPs and enhancing the affinity between SiO 2 and ZrO 2 .