Jump to main content
Jump to site search

Issue 4, 2019
Previous Article Next Article

A comparative study of mechanisms of the adsorption of CO2 confined within graphene–MoS2 nanosheets: a DFT trend study

Author affiliations

Abstract

The space within the interlayer of 2-dimensional (2D) nanosheets provides new and intriguing confined environments for molecular interactions. However, atomic level understanding of the adsorption mechanism of CO2 confined within the interlayer of 2D nanosheets is still limited. Herein, we present a comparative study of the adsorption mechanisms of CO2 confined within graphene–molybdenum disulfide (MoS2) nanosheets using density functional theory (DFT). A comprehensive analysis of CO2 adsorption energies (EAE) at various interlayer spacings of different multilayer structures comprising graphene/graphene (GrapheneB) and MoS2/MoS2 (MoS2B) bilayers as well as graphene/MoS2 (GMoS2) and MoS2/graphene (MoS2G) hybrids is performed to obtain the most stable adsorption configurations. It was found that 7.5 Å and 8.5 Å interlayer spacings are the most stable conformations for CO2 adsorption on the bilayer and hybrid structures, respectively. Adsorption energies of the multilayer structures decreased in the following trend: MoS2B > GrapheneB > MoS2G > GMoS2. By incorporating van der Waals (vdW) interactions between the CO2 molecule and the surfaces, we find that CO2 binds more strongly on these multilayer structures. Furthermore, there is a slight discrepancy in the binding energies of CO2 adsorption on the heterostructures (GMoS2, MoS2G) due to the modality of the atom arrangement (C–Mo–S–O and Mo–S–O–C) in both structures, indicating that conformational anisotropy determines to a certain degree its CO2 adsorption energy. Meanwhile, Bader charge analysis shows that the interaction between CO2 and these surfaces causes charge transfer and redistributions. By contrast, the density of states (DOS) plots show that CO2 physisorption does not have a substantial effect on the electronic properties of graphene and MoS2. In summary, the results obtained in this study could serve as useful guidance in the preparation of graphene–MoS2 nanosheets for the improved adsorption efficiency of CO2.

Graphical abstract: A comparative study of mechanisms of the adsorption of CO2 confined within graphene–MoS2 nanosheets: a DFT trend study

Back to tab navigation

Supplementary files

Publication details

The article was received on 28 Oct 2018, accepted on 04 Jan 2019 and first published on 14 Jan 2019


Article type: Paper
DOI: 10.1039/C8NA00314A
Nanoscale Adv., 2019,1, 1442-1451
  • Open access: Creative Commons BY-NC license
  •   Request permissions

    A comparative study of mechanisms of the adsorption of CO2 confined within graphene–MoS2 nanosheets: a DFT trend study

    F. M. Enujekwu, C. I. Ezeh, M. W. George, M. Xu, H. Do, Y. Zhang, H. Zhao and T. Wu, Nanoscale Adv., 2019, 1, 1442
    DOI: 10.1039/C8NA00314A

    This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. Material from this article can be used in other publications provided that the correct acknowledgement is given with the reproduced material and it is not used for commercial purposes.

    Reproduced material should be attributed as follows:

    • For reproduction of material from NJC:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the Centre National de la Recherche Scientifique (CNRS) and the RSC.
    • For reproduction of material from PCCP:
      [Original citation] - Published by the PCCP Owner Societies.
    • For reproduction of material from PPS:
      [Original citation] - Published by The Royal Society of Chemistry (RSC) on behalf of the European Society for Photobiology, the European Photochemistry Association, and RSC.
    • For reproduction of material from all other RSC journals:
      [Original citation] - Published by The Royal Society of Chemistry.

    Information about reproducing material from RSC articles with different licences is available on our Permission Requests page.

Search articles by author

Spotlight

Advertisements