A General Synthetic Approach for Integrated Nanocatalysts of Metal-Silica@ZIFs

Abstract

Integration of different nanocomponents into a greater assemblage or object for applications poses a significant challenge to materials chemists. At present, it still remains extremely difficult to achieve high monodispersivity for such assembled products. To gain better synthetic controllability, ideally, an integration of this type should be done in a stepwise manner. Herein, we report a versatile stepwise approach for preparation of integrated nanocatalysts of metal-mSiO2@ZIFs (metal = Pt, Pd, Ru, Ag, and Pt53Ru47; mSiO2 = mesoporous silica; and ZIFs = ZIF-8 and ZIF-67). Starting with uniform solid Stober silica spheres in submicrometer scale, mesoporous channels with desired length and diameter can be created for silica which serves as a support. With measurements of amino-modification of mesopores and selection of metal precursors applied, subsequently, ultrafine metal nanoparticles (2–5 nm) can be deposited evenly onto the inner walls of silica channels. Resultant metal-mSiO2 spheres are then modifi...