Hydrothermal Rearrangement and Postsynthesis Treatment

In most cases, a typical sol-gel mesoporous material is prepared under hydro-thermal conditions the surfactant is dissolved in a solvent (commonly water), the molecular precursors are added to this solution followed by the appropriate catalyst (acid or base), the sol and the resulting gel are allowed to form, the composite material is heated, and finally the template is removed (by calcination or extraction) to generate a mesoporous material. A microwave-hydrothermal 

To conclude, when it comes to hydrothermal treatment, a lot of structural modification can occur depending on the experimental conditions. The key parameter in these structural changes is the flexibility of the silicate network. Apart from hydrothermal treatment, numerous other postsynthesis treatments have been described in order to reduce the pore size [21] or improve structural order, hydrothermal stability, and other characteristics of the mesoscopic materials [lOd]. 

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