Oligopyrrole Complexes (neutral, III) for biogas capture applications by DFT
Marisol Ibarra-Rodríguez,1* Mario Sánchez2*
1Universidad Autónoma de Nuevo León, Facultad de Ciencias Químicas, Ciudad Universitaria, 66451, Nuevo León, México
2Centro de Investigación en Materiales Avanzados, S.C., Alianza Norte 202, PIIT, Carretera Monterrey-Aeropuerto Km. 10, C. P. 66628, Apodaca, Nuevo León, México.
* E-mail:mibarod_22@hotmail.com(Marisol Ibarra-Rodríguez), mario.sanchez@cimav.edu.mx (Mario Sánchez)
Abstract:
The structures and interactions of systems formed by the MPBCP (meta-Phenylene-Bridged Cyclic Oligopyrrole) functionalized with lanthanum atom were studied for investigating the abilities of MPBCP, [La-MPBCP]+3 and La-MPBCP to absorb biogas (CO2, N2, H2 and CH4) using density functional theory. TheEads calculated values for biogas molecules on [La-MPBCP]+3 and La-MPBCP showed that these gas molecules have favorable interactions with the lanthanum atom coordinated on the MPBCP. CO2 molecule shows strong interactions, with Eads values of -28.63 and -15.95 kcal/mol. In the case of H2 molecule, theEads is lower with values of -7.51 and -5.28. It is easy to observe the CO2 molecule on the [La-MPBCP]+3 system has four times higher energy value than adsorption energy for the H2 molecule. The natural bond orbital analysis reveals that gas molecules are electron donator in the systems and the acceptor orbitals belong to lanthanum atom. Computational studies suggest that CO2, N2, CH4 and H2 molecules on [La-MPBCP]+3 and La-MPBCP present physisorption. Our findings divulge promising potential of the [La-MPBCP]+3 as an adsorber/separator CO2/H2.