Work

Resolving and Controlling Silicoaluminophosphate Zeolite Intergrowths and Mixtures

Year: 2026

Type: article

Abstract: Achieving controlled synthesis of silicoaluminophosphate (SAPO) zeolites is critical for optimizing their catalytic performances, yet it remains difficult due to the complex coupling of synthesis variables and insufficient atomic-level structural understanding. Herein, we systematically investigate the multi-scale characterization and controllable synthesis of SAPO zeolites. We explore the effects of critical synthesis parameters (pH, Si content, the concentration and composition ratio of structure-directing agents) on the structural selectivity and distribution of SAPO-5 (AFI) and SAPO-34/18 (CHA/AEI) intergrowths and mixtures, identify the selective synthesis window for each structural component, and interpret the underlying selectivity mechanism from a perspective of competitive thermodynamics and kinetics. Low-dose electron microscopy enables the atomic-resolution imaging of beam-sensitive SAPO-34/18 intergrowths for revealing their stacking sequences and spatial distributions under the regulation of Si content and structure-directing agent ratio. This work provides a methodology for investigating the structure-property relationship of zeolite structures by combining controllable synthesis with atomic-resolution electron microscopy, thereby enabling the controllable design of these zeolite catalysts with tailored topology and porous structure.

Source: Advanced Science

DOI: 10.1002/advs.76192