Design and Synthesis of a Medium-pore Aluminosilicate Zeolite SCM-53

Designing and synthesizing condensed, thermally stable zeolite structures by inverse sigma expansion of open-framework zeolites has been well achieved. While creating open-framework, thermally stable zeolites through sigma expansion of condensed frameworks remains rare. Herein, we present the rational design and synthesis of a thermally stable medium-pore aluminosilicate zeolite SCM-53, which possesses a two-dimensional (2D) 10 × 10-ring channel system. The framework of SCM-53 was theoretically predicted by sigma expansion of the framework of SCM-51, a small-pore aluminosilicate zeolite featuring a 2D 8 × 8-ring channel system prepared by calcination of the layered precursor SCM-50. SCM-53 was rationally synthesized by successive interlayer silylation and calcination treatments of SCM-50. The structure of SCM-53 was validated by powder X-ray diffraction (PXRD), scanning transmission electron microscopy (STEM), nuclear magnetic resonance (NMR) spectroscopy, etc. Our results demonstrate that SCM-53 possesses accessible micropores (5.7 Å), an ultrathin nanosheet morphology (~15 nm), and high thermal stability (up to 1000 ℃), suggesting its potential for adsorption and catalytic applications.