Fabrication of highly uniform ultra-small zeolite T nanocrystals

Ultra-Small Nanosized zeolite T crystals with an average size of about 16 nm were successfully obtained from freshly prepared NaAlO2 using Al powder at a low crystallization temperature of 60 °C, while the commercial NaAlO2 led to the amorphous product. The nanocrystals prepared from Al powder were pure and uniform, evidenced by XRD, SEM, and TEM. The prepared zeolite T crystals showed highest CO2 adsorption capacity (73.19 cm3/g STP) and high CO2/N2 IAST selectivity (47.62) at 1 bar at 25 °C, indicating its high CO2 adsorption potential. The freshly prepared NaAlO2 by Al powder led to much smaller crystals than commercial NaAlO2 at a higher crystallization temperature. This work demonstrates a simple and effective approach for the achievement of ultra-small zeolite T nanocrystal, providing the possibility for manipulation of ultrathin zeolite membrane or film.