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Influence of the Template Removal Method on the Mechanical Stability of SBA‐15

ABSTRACT: Abstract Removing the template from the pores after the polycondensation of the silica precursor is a necessary step in the synthesis of mesoporous silica materials. In our previous work, we developed a method for the efficient and spatially controlled functionalization of SBA‐15. First, the silanol groups on the particle surface and in the pore entrances were passivated. After extraction of the template, a pretreatment step in N2 converted the silanol groups to the single and geminal state. Afterwards, an azide functionality was introduced exclusively into the mesopores. This ensured that the catalyst could afterwards be immobilized unambiguously in the mesopores. The mechanical stability of a material functionalized in such a spatially controlled manner is studied and compared to other template removal methods. Even though several studies investigated the influence of the calcination temperature, the presence or the absence of oxygen during the template removal, the specific conditions used during the herein reported selective functionalization procedure have not been covered yet. Removing the template from mesoporous SBA‐15 by calcination in air was evaluated against Soxhlet extraction with ethanol, followed by pretreatment at 550 °C in N2, with regard to the mechanical stability of the materials. Pressures of 39 and 156 MPa were applied. The results are relevant for the stepwise selective functionalization, as the removal of the template without a calcination step allows for a more time‐ and material‐efficient functionalization procedure.

SUBMITTER: Beurer A

PROVIDER: S-EPMC8569929 | biostudies-literature |

REPOSITORIES: biostudies-literature

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