Efficient capture of CO ₂ over ordered micro-mesoporous hybrid carbon nanosphere

Four kinds of carbon-based adsorbents (micro-mesoporous hybrid carbon nanosphere and N-doped hollow carbon sphere with single-, double- or ruga-shell morphology) with different structural and textural properties were prepared and systematically studied in CO ₂ capture. All synthesized samples possess high specific surface area (828–910 m ² g ⁻¹ ), large pore volume (0.71–1.81 cm ³ g ⁻¹ ), and different micropore contents varied from 2.1% to 46.4%. Amongst, the ordered micro-mesoporous carbon nanosphere (OM-CNS) exhibits the best adsorption performance with CO ₂ uptake as high as 3.01 mmol g ⁻¹ under conditions of 298 K and 1.0 bar, better than most of the reported CO ₂ adsorbents. The excellent CO ₂ adsorption capacity of OM-CNS can be reasonably attributed to the synergistic effect of ordered mesopore channels and abundant structural micropores which are beneficial for the diffusion and trapping of CO ₂ adsorbate. Moreover, the OM-CNS shows excellent CO ₂ trapping selectivity and superior stability and recyclability, which endow the OM-CNS as a promising and environmental-friendly adsorbent for CO ₂ capture and separation under practical conditions.