A General Route to Flame Aerosol Synthesis and In Situ Functionalization of Mesoporous Silica

Abstract

Mesoporous silica is a versatile material for use in catalysis and adsorption in energy, environmental, and medical applications. Here, for the first time, we report a flame aerosol synthesis method for a class of mesoporous silica materials with hollow, amorphous structure, low density, and specific surface area exceeding 1000 m 2 /g. We show its superior performance vs. MCM-41 in properties relevant to water purification, drug carrier, and thermal insulation applications. Moreover, we produced several types of mesoporous silica-supported nano-catalysts by in situ incorporation of active metals. The generality of this method is demonstrated by decorating mesoporous supports with noble metal, transition metal, and metal oxide nanoclusters, including Pt/SiO 2 , Ni/SiO 2 , CrO 3 /SiO 2 , and Co/Al 2 O 3 . As a prototypical application, we demonstrate dry reforming of methane using Ni/SiO 2 , achieving constant 97% CH 4 and CO 2 conversions for more than 200 hours, dramatically outperforming a corresponding MCM-41 supported Ni catalyst. Thus, this work provides a continuous and scalable strategy to produce mesoporous silica nanoshells, and the proposed in situ functionalization mechanism may pave the way to flexible catalysts for a diverse range of reactions.

Mesoporous Silica Nanoparticles‐Based Nanoplatforms: Basic Construction, Current State, and Emerging Applications in Anticancer Therapeutics

“…B) HAADF‐STEM and elemental mapping images of Pt/SiO 2 with hollow structure (adapted with permission. [ 71 ] Copyright 2022, John Wiley and Sons Ltd). C) TEM image and element mapping images of the hollow‐structured silica composites ZIF‐8@SiO 2 (adapted with permission.…”

“…[ 70 ] Recently, Mark T. Swihart reported for the first time a flame aerosol synthesis method for a class of mesoporous silica with a hollow structure (Figure 2B) and a specific surface area exceeding 1000 m 2 g −1 . [ 71 ] The synthesis is based on an unconventional flame reactor configuration to produce mesoporous silica nanoshells in a continuous flame aerosol process. During the synthesis, the H 2 ‐rich flame generates a high temperature (600–850 °C) in the reaction chamber, which drives the evaporation and reaction.…”

“…Copyright 2021, American Chemical Society). B) HAADF-STEM and elemental mapping images of Pt/SiO 2 with hollow structure (adapted with permission [71]. Copyright 2022, John Wiley and Sons Ltd).…”