Creation of hollow SAPO-34 single crystals via alkaline or acid etching

Abstract

Hollow SAPO-34 crystals are created via selective etching of their precursor under controlled alkaline or acid conditions. The abundant/interconnected Si-O-Al domains and Si-O-Si networks at the outer layer of SAPO-34 crystals are revealed to be decisive factors for the base and acid treatments respectively to achieve a well-preserved hollow structure.