Methane adsorption in ADOR zeolites: a combined experimental and DFT/CC study.

Area of Science:

• Materials Science
• Physical Chemistry
• Nanotechnology

Background:

• Recent advancements in zeolite synthesis enable the creation of novel 2D materials.
• Understanding gas adsorption in these materials is crucial for applications like carbon capture and storage.

Purpose of the Study:

• To investigate the physical adsorption of methane in purely siliceous molecular sieves synthesized using 2D zeolites.
• To validate a Density Functional Theory/Coupled Cluster (DFT/CC) based computational method for characterizing these nanomaterials.

Main Methods:

• Combined experimental adsorption measurements and theoretical calculations (DFT/CC).
• Testing the methodology on ADOR zeolites (UTL family) and other well-characterized siliceous zeolites (OKO, PCR, MFI, CHA, AEI).
• Analysis of discrepancies using a defect model (D4R defects).

Main Results:

• Excellent agreement between theoretical and experimental heats of methane adsorption for OKO, PCR, MFI, CHA, and AEI zeolites.
• A minor discrepancy for UTL germanosilicate was explained by D4R defects.
• The DFT/CC method proved reliable for the studied siliceous zeolites.

Conclusions:

• The validated DFT/CC methodology serves as a reliable characterization tool for newly synthesized silica nanomaterials.
• This approach aids in understanding and optimizing methane adsorption in advanced zeolite structures.
• The findings contribute to the development of materials for gas storage and separation applications.