Template removal from mesoporous silicas using different methods as a tool for adjusting their properties

Abstract

Use of three detemplation schemes (calcination, extraction and H2O2 treatment) led to materials with different structures and surface chemistry (content of silanol groups), which affected their adsorption performance towards l-histidine.

Non-thermal plasma: A fast and efficient template removal approach allowing for new insights to the SBA-15 structure

“…Hence, in the scientific literature SBA-15 materials are usually calcined at temperatures between 400 and 600 °C in order to totally eliminate the template. [6][7][8]10,16 Yet, calcination temperature has a major impact on the textural properties of the SBA-15 materials.…”

“…The liquid extractions with solvents 14 or supercritical fluid extraction with CO 2 15 are appealing strategies as templates can be recovered and hence recycled, yet templating removal efficiency is limited to 60-80% even after various extraction cycles, which implies the necessity of further treatments. Besides calcination, oxidative treatments based on the digestion with H 2 O 2 , [16][17][18][19] and plasma assisted template degradation have been reported for the elimination of Pluronic templated silicas. Saito and co-workers developed a solution plasma process in which active species based on O, H and OH in situ develop from the aqueous solution.…”

Mesoporous silica films for sensing volatile organic compounds using attenuated total reflection spectroscopy

“…Note that surfactant removal can also be achieved by other, low-temperature treatments. 32,47 X-ray diffraction proved the periodic arrangement of the mesoporous films (see ESI). The formation of silica, complete removal of the template and successful surface functionalization was confirmed by FTIR measurements.…”

Novel porous organocatalysts for cycloaddition of CO2and epoxides

“…On the other hand, template removal by solvent extraction minimizes framework shrinkage, leading to higher surface area, pore volume and number of silanols compared to its calcined counterpart. 40,41 The capillary condensation of all DMOs and OMOs were observed to be less sharp compared to their corresponding supports and SBA-15*, respectively; an indication of decreased pore size. This provided further evidence that immobilization of the organic moieties took place on the internal surface of the supports.…”