Enhanced pore structure regulation in porous aromatic framework materials via montmorillonite templating

Abstract

The specific regulation of pore structure in porous aromatic framework (PAF) materials is of paramount importance for achieving exceptional performance. In this study, we propose a novel approach by utilizing the two-dimensional layered mineral, montmorillonite, as a template for the synthesis of PAF-Mt. Through a meticulously designed hydrothermal method, the residual template is completely eliminated, resulting in the creation of a new porous aromatic framework material, termed PAF-Mt-Free. Our research findings demonstrate remarkable improvements in the morphology, surface area, and pore size of PAF-Mt-Free compared to classical PAFs. Specifically, the morphology of PAF-Mt-Free undergoes a transformation from spherical to smaller fragmented particles. The specific surface area （968.163 m2/g） is enhanced by 47.9% compared to PAF-Mt（654.784 m2/g） and by 68.3% compared to PAF-45（575.390 m2/g）. Moreover, the main pore size of PAF-Mt-Free increases from approximately 0.5 nm to 0.9 nm. Importantly, PAF-Mt-Free not only maintains the excellent photocatalytic performance of PAF-Mt but also exhibits significantly enhanced adsorption capacity, particularly for organic molecules with a size smaller than 1 nm. Notably, the adsorption efficiency for benzene, toluene, chlorobenzene, and bromobenzene increases by 10%, 18.4%, 11%, and 13.2%, respectively. These findings highlight the promising potential of utilizing montmorillonite templating for the precise control of pore structure in PAF materials, leading to enhanced adsorption performance. Our study contributes to the advancement of porous aromatic framework materials and their applications in various fields.