Unraveling templated-regulated distribution of isolated SiO 4 tetrahedra in silicoaluminophosphate zeolites with high-throughput computations.

Silicoaluminophosphate (SAPO) zeolites are well-known catalytic materials because of the mild acidity originating from the isolated SiO 4 tetrahedra in their frameworks. Regulating the distribution of isolated SiO 4 tetrahedra in SAPO zeolites is formidably challenging because SiO 4 tetrahedra tend to agglomerate to form Si islands and the isolated SiO 4 tetrahedra are difficult to determine using conventional characterization techniques. Here we synthesized Si-island-free SAPO-35 zeolites by using N -methylpiperidine as a new template, which exhibited excellent thermal stability compared to conventional SAPO-35 zeolites and a substantially improved methanol-to-olefins catalytic lifetime even comparable to that of commercial SAPO-34 zeolites. More strikingly, with the aid of high-throughput computations on 44 697 structure models combined with various state-of-the-art characterization techniques, for the first time, we reveal that the host-guest interactions between template molecules and SAPO frameworks determine the specific distributions of isolated SiO 4 tetrahedra, which are responsible for the improvement in the chemical properties of zeolites. Our work provides an insight into the template-based regulation of isolated SiO 4 tetrahedra in SAPO zeolites, which opens a new avenue in the discovery of promising zeolite catalysts with optimal SiO 4 distribution.