Incorporation of metal organic framework into mesoporous silica nanoparticles with high contents

The integration of mesoporous silica materials (MSMs) and metal organic frameworks (MOFs) has garnered significant attention. To date, various strategies have been developed to synthesize MSM-MOF composites. However, it is challenging to synthesize MSM-MOF with high MOF contents (e.g., metal to silica molar ratio above 0.4) and well maintained mesopores. Here, we report a metal oxide conversion strategy for the synthesis of dendritic mesoporous silica nanoparticles (DMSNs)-MOF nanocomposites with a high MOF content, using zinc-based MOFs as examples. By adjusting the amount of zinc salts and the reaction time, DMSN-ZIF-8 can be prepared with a zinc to silicon molar ratio up to 0.4-0.8:1, and the mesopores can be reserved at the zinc to silicon ratio of 0.4. This strategy can be further applied to synthesize DMSN-ZIF-90 nanocomposites. This work has provided a robust strategy for the synthesis of MSM-MOF composites with adjustable compositions and nanostructures.