AbstractSulfur hexafluoride (SF6) is an extremely potent greenhouse gas, motivating the development of energy-efficient SF6/N2 separation technologies. Herein, a high-throughput computational screening of 12,020 metal organic frameworks (MOFs) and 561 covalent organic frameworks (COFs) was conducted to evaluate their separation performance under temperature swing adsorption (TSA) conditions. The results indicate that adsorption performance is jointly governed by structural parameters and the isosteric heat of adsorption (Qst), with optimal performance achieved within specific parameter ranges. Although MOFs and COFs exhibit similar structural preferences, their adsorption mechanisms differ in the origin of host–guest interactions: MOFs typically achieve higher Qst values due to open metal or oxygen sites, whereas COFs rely more strongly on pore-geometry-driven confinement combined with moderate adsorption energies. In both material classes, superior SF6/N2 separation performance is generally associated with relatively higher Qst values, although the absolute Qst of MOFs remains higher than that of COFs. Representative candidates, MARJAQ and LZU-111, exhibit SF6 adsorption capacities of 8.27 and 6.19 mmol·g−1 and selectivities of 568.93 and 2100.21 at 298 K and 1 bar, respectively. These findings establish quantitative structure–property relationships and design guidelines for porous adsorbents.
Distinct adsorption mechanisms of MOFs and COFs for SF6/N2 separation revealed by high-throughput TSA screening
Boaro M.;
2026-01-01
Abstract
AbstractSulfur hexafluoride (SF6) is an extremely potent greenhouse gas, motivating the development of energy-efficient SF6/N2 separation technologies. Herein, a high-throughput computational screening of 12,020 metal organic frameworks (MOFs) and 561 covalent organic frameworks (COFs) was conducted to evaluate their separation performance under temperature swing adsorption (TSA) conditions. The results indicate that adsorption performance is jointly governed by structural parameters and the isosteric heat of adsorption (Qst), with optimal performance achieved within specific parameter ranges. Although MOFs and COFs exhibit similar structural preferences, their adsorption mechanisms differ in the origin of host–guest interactions: MOFs typically achieve higher Qst values due to open metal or oxygen sites, whereas COFs rely more strongly on pore-geometry-driven confinement combined with moderate adsorption energies. In both material classes, superior SF6/N2 separation performance is generally associated with relatively higher Qst values, although the absolute Qst of MOFs remains higher than that of COFs. Representative candidates, MARJAQ and LZU-111, exhibit SF6 adsorption capacities of 8.27 and 6.19 mmol·g−1 and selectivities of 568.93 and 2100.21 at 298 K and 1 bar, respectively. These findings establish quantitative structure–property relationships and design guidelines for porous adsorbents.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
