Programme

O.15 -- Oral, VCTP-48

Date: Thursday, 3 August 2023

Time: 14:40 - 15:05

Computational Study of the Adsorption of Small Gas Molecules on Pillar[n]arenes

Quoc Duy Ho and Eva Rauls

Stavanger University, Norway

The adsorption of small gases (CO2, N2, CH4) by Pillar[5]arenes (P[5]A) was studied using DFT-based methods. Small gases can be adsorbed by P[5]A at the cavity site or at a hydroxyl group. π-π interactions and weak hydrogen bonds are the major contributors to adsorption at the cavity site and OH groups, respectively. Calculated results also demonstrate the selectivity of CO2 over N2 and CH4 in P[5]A adsorption. The effects of P[n]A cavity sizes (n=4, 5, and 6) on CO2 adsorption were also studied. Due to charge transfer from the four aromatic rings, CO2 adsorption at the cavity site has the highest binding energy at P[4]A, while the adsorption at hydroxyl groups has similar binding energies on P[4]A, P[5]A, and P[6]A. The number of CO2 molecules that can be adsorbed at the cavity site depends on the P[n]A cavity size; the larger the cavity, the more CO2 molecules can be adsorbed before saturation occurs. P[6]A is the optimal choice for selective CO2 adsorption quantity. The density of state calculations show the physical adsorption of gases in P[n]A. Therefore, if P[n]A is used for gas adsorption, it can be reused after suitable desorption.

Presenter: Ho Quoc Duy