Micromeso Hierarchical Porous Ultrathin Nitrogen-Doped Carbon Nanosheets with Rough Surfaces for Efficient Gas Adsorption and Separation

The development of advanced high-efficiency adsorbents is the key to promoting the iterative progress of gas separation and capture technology. Herein, a series of N-doped ultrathin carbon nanosheets (Zn-NDPCs) with a micromeso hierarchical connected porous structure are synthesized by directly annealing Zn-poly­(4-vinylpyridine) coordination compounds. Among them, Zn-NDPC-500 has a high surface area (1146 m2 g–1), rich N-doped active sites, and unimodal ultramicropores (0.5 nm). The thickness of Zn-NDPC-500 is only 3.8 nm, and it has rough surface morphology. Benefiting from the synergy of the above structures on the interaction between gas molecules and materials, Zn-NDPC-500 shows excellent adsorption capacity for C2H2 (3.2), C2H6 (2.7), C3H8 (4.8), and CO2 (2.5 mmol g–1) and high ideal adsorbed solution theory (IAST) selectivity for C2H2/CH4, C2H6/CH4, C3H8/CH4, CO2/CH4, and CO2/N2 as high as 33.4, 20.3, 404.6, 11.3, and 63.9, respectively, under ambient conditions.