| Abstract
| - Phase transformation of mesoporous silica during the drying process is investigated. As-synthesized hexagonal p6mm obtained under the conditions used in this study is transformed to cubicIa3d as drying proceeds, even at room temperature. Prolonged synthesis results in the formation of awell-ordered hexagonal mesophase, with almost no phase transformation. Drying at a higher temperaturepromotes the phase transformation of not only hexagonal to cubic, but also cubic to lamellar mesophases.Release of water is detected during drying, which is followed by the phase transformation of the mesophases.The phase transformations observed here proceed against the direction estimated on the basis of thestate-of-the-art understanding. Here, considering the degree of silicate condensation and the amount ofresidual water in the as-synthesized mesoporous silica, a comprehensive explanation of mesophasedetermination is proposed including thermodynamic and kinetic aspects to account for the results observedhere and those in the literature.
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