Judicious design functionalized 3D‐COF to enhance CO2 adsorption and separation

• Published in: Journal of computational chemistry Vol. 42; no. 13; pp. 888 - 896
• Main Authors: Yuan, Fang, Yang, Zhifang, Zhang, Xiaoying, Tong, Cuiyan, Gahungu, Godefroid, Li, Wenliang, Zhang, Jingping
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 15.05.2021; Wiley Subscription Services, Inc
• Subjects: Adsorption; Carbon dioxide; Carbon sequestration; CO2 adsorption; Density functional theory; Functional groups; functionalized COF; GCMC; Low pressure; Pore size; Porosity; Selectivity; Separation
• ISSN: 0192-8651; 1096-987X
• DOI: 10.1002/jcc.26510

ABSTRACT The effects of functional groups (including OH, OCH3, NH2, CH2NH2, COOH, SO3H, OCO(CH2)2COOH(E‐COOH), and (CH2)4COOH(c‐COOH)) in 3D covalent organic frameworks (3D‐COFs) on CO2 adsorption and separation are investigated by grand canonical Monte Carlo (GCMC) simulations and density functional theory calculations. The results indicate that interaction between CO2 and the framework is the main factor for determining CO2 uptakes at low pressure, while pore size becomes the decisive factor at high pressure. The binding energy of CO2 with functionalized linker is correlated to CO2 uptake at 0.3 bar and 298 K on 3D‐COF‐1, suggesting functional groups play a key role in CO2 capture in microporous 3D‐COFs. Moreover, CO2 selectivity over CH4, N2, and H2 can be significantly enhanced by functionalization, where CH2NH2, COOH, SO3H, and E‐COOH enhance CO2 adsorption more effectively at 1 bar. Among them, SO3H is the most promising functional group in 3D‐COFs for CO2 separation. Functionalized COFs are designed to enhance CO2 capture and selectivity and sulfonic acid group modified COF shows the best prospects.