A Designed Template Removal Method for Obtaining Mesoporous Films with Highly Ordered Structure by Rapid Thermal Processing Technique

The soft-templating methodology is a highly effective approach to prepare ordered organic mesoporous structures. However, in the traditional thermal-induced template removal process, the resultant mesoporous films often suffer from severe shrinkage, which causes a reduction in pore size and order. To overcome these limitations, we developed a strategy that combines rapid thermal processing (RTP) with dynamic circulation. This approach aims to optimize the ordered mesostructures of the films after template removal. The mesoporous structure was evaluated by various analytical techniques, including XRD, NMR, TEM, and grazing incident small angle X-ray scattering (GISAXS). Our results demonstrate that the dynamic thermal processing method leads to a high-quality mesoporous films with significantly reduced shrinkage in the mesoporous structure. Specifically, the d-spacing of mesopores decreased only from 10.4 to 9.1 nm when treated with RTP, which is smaller than the mesoporous films treated using traditional heat processing (reduced to 7.7 nm). Furthermore, dynamic cycling led to an increase in the domain size of the ordered structure from 49.1 to 199.7 nm. These findings were confirmed by cross-sectional TEM, consistent with the values obtained from the GISAXS analysis. Finally, we discuss the feasibility and efficiency of the proposed thermal treatment method, which can provide a straightforward approach to improve the ordered degree in mesoporous films.