Fig. 4.

Examples of CO₂ capture by solid sorbents. (A) Self-assembly of Fe-MOR monoliths. Shown are schematic illustrations of the synthetic procedure (a) and a side view (b) and top view (c) of precisely narrowed microchannels (kinetic diameter: 3.3 to 3.4 Å) by occupying isolated tetrahedral Fe species inside the 12-MR MOR microchannel. Blue indicates Si or Al, red is O, light brown is Fe, and gray is C (From ref. [94]. Reprinted with permission from AAAS). (B) Schematic diagram of enhanced CO₂ adsorption capacity with well-defined hierarchical porous carbon with ultramicropore-mesopore interconnected pore architectures (Reprinted from ref. [93], Copyright (2022), with permission from Elsevier).