Hierarchically porous and single Zn atom-embedded carbon molecular sieves for H2 separations
Leiqing Hu, Won‐Il Lee, Soumyabrata Roy, Ashwanth Subramanian, Kim Kisslinger, Lingxiang Zhu, Shouhong Fan, Sooyeon Hwang, Vinh T. Bui, Thien Tran, Gengyi Zhang, Yifu Ding, Pulickel M. Ajayan, Chang‐Yong Nam, Haiqing Lin
Abstract
Abstract Hierarchically porous materials containing sub-nm ultramicropores with molecular sieving abilities and microcavities with high gas diffusivity may realize energy-efficient membranes for gas separations. However, rationally designing and constructing such pores into large-area membranes enabling efficient H 2 separations remains challenging. Here, we report the synthesis and utilization of hybrid carbon molecular sieve membranes with well-controlled nano- and micro-pores and single zinc atoms and clusters well-dispersed inside the nanopores via the carbonization of supramolecular mixed matrix materials containing amorphous and crystalline zeolitic imidazolate frameworks. Carbonization temperature is used to fine-tune pore sizes, achieving ultrahigh selectivity for H 2 /CO 2 (130), H 2 /CH 4 (2900), H 2 /N 2 (880), and H 2 /C 2 H 6 (7900) with stability against water vapor and physical aging during a continuous 120-h test.