Precise regulation of CO2 packing pattern in s-block metal doped single-layer covalent organic frameworks for high-performance CO2 capture and separation

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

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Author(s)

  • Sainan Zhou
  • Shuxian Wei
  • Zhaojie Wang
  • Siyuan Liu
  • Daofeng Sun
  • Xiaoqing Lu

Detail(s)

Original languageEnglish
Article number135903
Journal / PublicationChemical Engineering Journal
Volume441
Online published26 Mar 2022
Publication statusPublished - 1 Aug 2022

Abstract

The development of high-performance CO2 capture and separation adsorbents is critical to alleviate the deteriorating environmental issues. Herein, six s-block metal doped single-layer polymeric tetraoxa[8]circulene (SBM-TOCs, SBM = Li, Na, K, Be, Mg, and Ca) were introduced as potential CO2 capture and separation adsorbents via precise regulation of CO2 packing patterns. Structural analyses showed that Li-TOC, Na-TOC, K-TOC, and Ca-TOC were screened with high cohesive energies ranging from 7.02 to 7.08 eV/atom and moderate formation energies ranging from –2.92 to –1.41 eV, guaranteeing their structural stabilities for CO2 capture and separation. Electronic structure analyses confirmed the large charge transfer and strong covalent bonding characters between the SBMs and direct-connected O atoms, thus constructing a favorable gas adsorption environment. Li-TOC exhibited an ultrahigh CO2 adsorption capacity of 10.78 mmol/g at 298 K and 1.0 bar, which was superior to previously reported Li-doped adsorbents. At 298 K and 1.0 bar, the selectivity of CO2 over N2/CH4 in Li-TOC reached up to ∼ 516 and ∼ 821, respectively. Polarity regulation analyses showed that SBMs had a more positive effect on the framework affinity for CO2 than N2/CH4 via both coulomb and van der Waals interactions. Space regulation analyses showed that strong interactions between the electropositive SBMs and the electronegative O atoms of CO2 facilitated vertical CO2 configurations and compact distributions, thereby rendering a multilayer CO2 adsorption and enhancing the CO2 adsorption capacity. Results of this work highlighted SBM-TOCs as ultrahigh-performance adsorbents for CO2 capture and separation over N2/CH4, and demonstrated that the precise regulation of CO2 packing pattern was an effective strategy to achieve high-performance gas capture and separation.

Research Area(s)

  • Precise regulation, S-block metal, Covalent organic framework, Packing pattern, CO2 capture and separation

Citation Format(s)

Precise regulation of CO2 packing pattern in s-block metal doped single-layer covalent organic frameworks for high-performance CO2 capture and separation. / Zhou, Sainan; Wang, Maohuai; Wei, Shuxian; Wang, Zhaojie; Liu, Siyuan; Wu, Chi-Man Lawrence; Sun, Daofeng; Lu, Xiaoqing.

In: Chemical Engineering Journal, Vol. 441, 135903, 01.08.2022.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review