Efficient CO2 capture by ZIF-8-derived in-situ nitrogen-doped nanoporous carbon with ultra-high selectivity and stability

Global warming and the increasing frequency of extreme weather caused by the gradual increase in CO 2 concentration in the atmosphere are urgent issues that must be addressed. In this study, ZIF-8-derived in-situ nitrogen-doped porous carbon materials were prepared through one-step pyrolysis of ZIF-8. The synthesis was gradually optimized by exploring different pyrolysis temperatures to determine the optimal ZIF-8-derived porous carbon for CO 2 adsorption. The CO 2 -adsorption capacity of ZIF-8–800 reached 5.22 and 6.19 mmol g −1 at 25 ℃ and 0 ℃ (1 bar), respectively. After five cycles, its CO 2 -adsorption capacity decreased by only about 1.7 %. Moreover, the CO 2 /N 2 selectivity at 1 bar was as high as 21.2 (48.9 at 0.05 bar), and the isothermal adsorption heat was also within a moderate range (31 kJ mol −1 ). The superior CO 2 adsorption performance was found to originate from the comprehensive effect of the three-dimensional pore structure that combined reasonably coordinated micropores, mesopores, and macropores, as well as some specific favorable N/O groups. The results indicate the broad application prospects of ZIF-8-Ts in CO 2 capture and separation and provide new ideas for the sustainable application of novel MOF-derived porous carbon materials.