Carbon Dots‐Induced Hydrogen‐Bonding Traps in RHO Zeolite: Mechanistic Insights and Superior Flue Gas Separation Performance

Abstract

Abstract Zeolites stand out as promising materials for flue gas separation, however, it poses a significant challenge to conduct pore interior modifications to improve the separation performance. Herein, we present a novel strategy for constructing hydrogen‐bonding traps in a small‐pore RHO zeolite by embedding carbon dots (CDs), thereby to regulate pore microenvironment and enhance the separation ability of CO 2 /N 2 . The incorporation of CDs into the RHO zeolite is realized via a straightforward calcination process, which endows the zeolite with the defect sites rich in hydroxyl groups that easily form hydrogen bonds with CDs. Along with 1 H‐ 1 H DQ‐SQ experiments, in situ FTIR and DFT calculations, the unique hydrogen‐bonding traps are unraveled, which can selectively capture and concentrate CO 2 . As a result, the CDs‐containing zeolite (R‐500) showcases exceptional performance in terms of both CO 2 adsorption (90.40 cm 3 g −1 at 298K and 1 bar) and CO 2 /N 2 (15/85) separation (IAST selectivity of 1063.6). Strikingly, a superior CO 2 adsorption with a capacity of 42.9 cm 3 g −1 is achieved in the dynamic separation process (CO 2 /N 2 15/85). The facile synthesis and impressive separation performance of R‐500 provides a promising solution for industrial scale CO 2 /N 2 separation in flue gas.