LAUSR

Zeolites are microporous silicates with a large variety of applications as catalysts, adsorbents, and cation exchangers. Stable silica-based zeolites with increased porosity are in demand to allow adsorption and processing of large molecules but challenge our synthetic ability. We report a new, highly stable pure silica zeolite called ZEO-3, which has a multidimensional, interconnected system of extra-large pores open through windows made by 16 and 14 silicate tetrahedra, the least dense polymorph of silica known so far. This zeolite was formed by an unprecedented one-dimensional to three-dimensional (1D-to-3D) topotactic condensation of a chain silicate. With a specific surface area of more than 1000 square meters per gram, ZEO-3 showed a high performance for volatile organic compound abatement and recovery compared with other zeolites and metal-organic frameworks. Description Condensing chains into extra-large pores Zeolites with extra-large pores could absorb and process larger molecules, but strategies for synthesizing these materials are limited. Li et al. show that a silicate precursor with one-dimensional chains can undergo condensation reactions upon heating to remove the organic template to form Si-O-Si bridges that maintain the crystal topology (see the Perspective by Morris). The resulting low-density, pure silica zeolite has 14- and 16-membered silicate rings and highly thermal and hydrothermal stability. —PDS Chain-condensation reactions in a chain silicate precursor form Si–O–Si bridges and an extra-large pore, low-density zeolite.