Development of poplar wood and metal-organic frameworks derived ZIF-8@Porous carbon composites for carbon dioxide adsorption

Metal-organic frameworks (MOFs) derived porous carbons have been demonstrated to have dramatic performance in CO 2 adsorption. Herein, ZIF-8 was initially synthesized in the pores of Chinese white poplar to prepare composites, and then the composites were carbonized into ZIF-8@Poplar porous carbon for CO 2 uptake. The structure and physical-chemical properties of the prepared material were investigated. The results showed that when the molar ratio of metal clusters to organic ligands was 1:4, the synthesized ZIF-8 had small particle size around 150–200 nm and was resistant to 973 K, this confirmed the feasibility for composite of ZIF-8@wood. ZIF-8 was successfully synthesized in situ inside of wood, it suspected combining with wood through hydrogen bonding and electrostatic interactions, and its content in wood was 12.76   %. The prepared ZIF-8@Poplar porous carbon was an amorphous carbon with BET surface area of 233.772 m 2 /g, pore volume of 0.177 cm 3 /g and the average pore size of 3.024 nm. It had CO 2 capacity of 1.33 mmol/g at 298 K at 1 bar with lower N content (based on XPS patterns), the CO 2 adsorption was conducted from its abundant micropores, which is corroborated by the heat of CO 2 adsorption (34.53 kJ/mol) calculated based on Clausius-Clapeyron equation. Based on Ideal Adsorbed Solution Theory (IAST), it has a good adsorption selectivity of CO 2 over N 2 on a gas mixture containing 10   % CO 2 and 90   % N 2 . In summary, in situ synthesis and co-carbonization provide a strategy for the synthesis of MOFs@wood-derived hard porous carbon for superior CO 2 uptake in industrial applications.