Theoretical studies of CO2 adsorption mechanism on linkers of metal-organic frameworks

► The adsorption mechanism of CO2 on linker of MOFs is investigated. ► The models are evaluated by comparing the adsorption energies. ► Eight different positions on linker with three orientations of CO2 are studied. ► Chemical modifications are conducted to enhance the adsorption strength of CO2. ► The highest adsorption energy is obtained by doping MOFs with Li atom.