Journal
ACS APPLIED ENERGY MATERIALS
Volume 5, Issue 5, Pages 6032-6042Publisher
AMER CHEMICAL SOC
DOI: 10.1021/acsaem.2c00439
Keywords
zeolites; flexibility; stability; cations; nanomaterials; adsorption
Funding
- Industrial Chair ANR-TOTAL Nanoclean Energy [IPA 5621]
- Label of Excellence for the Centre of Zeolites and Related Nanoporous Materials by the Region of Normandy
- Normandy Region through the RIN Recherche Program [18P01675]
- RIN Recherche DIXOS [18E01714/18P02440]
- TOTAL
Ask authors/readers for more resources
The engineering of RHO nanozeolite allows for tailoring of its particle morphology, Si/Al ratio, cation content, stability, and flexibility. The synthesis process was optimized to improve the Si/Al ratio while maintaining nanosized dimensions and well-defined morphology. In situ XRPD experiments demonstrate the unique structural behavior of the nanozeolites at high temperatures. The findings expand the scope of nanozeolites for precise applications.
The engineering of RHO nanozeolite is demonstrated by synthesis from a colloidal precursor suspension using only inorganic structure-directing agents (Na+, Cs+), whereby the particle morphology, Si/Al ratio, cation content, stability, and flexibility are tailored. RHO nanozeolite with a higher Si/Al ratio (2.0) and superior thermal stability (up to 700 degrees C) compared to previous reports is synthesized. Optimization of the synthesis procedure by introducing additional Si precursors facilitated the targeted improvement in the Si/Al ratio while maintaining the nanosized dimensions of the discrete zeolite crystals with well-defined rhombic dodecahedral morphology. The structural properties of the RHO nanozeolites are characterized by in situ variable-temperature X-ray powder diffraction (XRPD) experiments showing that the nanozeolites possess a single structural phase up to 740 degrees C; further heating to 760 degrees C induces a symmetry change from noncentrosymmetric to centrosymmetric associated with a large increase in the anisotropic displacement parameter of the Cs+ extra-framework cations. The structural behavior is unique compared to more siliceous Na+ and Cs+-containing RHO zeolites (Si/Al >= 3), which possess a centrosymmetric structure when hydrated. These experiments reveal a delineation, based on the Si/Al ratio and content of the extra-framework cations between the as-synthesized Na+ and Cs+-containing RHO zeolites that possess centrosymmetric or noncentrosymmetric symmetry when hydrated, as well as single or coexisting structural phases, expanding the scope of intelligently designed nanozeolites with tailored properties for precise applications.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available