Application of carbon nanostructures toward SO2 and SO3 adsorption: a comparison between pristine graphene and N-doped graphene by DFT calculations

• Published in: Journal of sulfur chemistry Vol. 37; no. 2; pp. 176 - 188
• Main Authors: Shokuhi Rad, Ali, Esfahanian, Mehri, Maleki, Sina, Gharati, Gelare
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 03-03-2016; Taylor & Francis Ltd
• Subjects: Adsorption; DFT; graphene; Graphite; N-doped graphene; nanostructure
• ISSN: 1741-5993; 1741-6000
• DOI: 10.1080/17415993.2015.1116536

We studied the adsorption of SO
x
(x = 2,3) molecules on the surface of pristine graphene (PG) and N-doped graphene (NDG) by density functional theory (DFT) calculations at the B3LYP/6-31G(d) level. We used Mulliken and NBO charge analysis to calculate the net charge transfer of adsorbed SO
x
on pristine and defected graphene systems. Our calculations reveal much higher adsorption energy and higher net charge transfer by using NDG instead of pristine graphene. Furthermore, the density of state (DOS) graphs point to major orbital hybridization between the SO
x
and NDG, while there is no evidence of hybridization by using pristine graphene. Based on our results, it is found that SO
2
and SO
3
molecules can be adsorbed on the surface of NDG physically and chemically with adsorption energies (E
ads
) of −27.5 and 65.2 kJ mol
−1
(19.6 and 51.4 kJ mol
−1
BSSE), respectively, while low adsorption energies were calculated in the case of using pristine graphene. So we introduced NDG as a sensitive adsorbent/sensor for detection of SO
2
and SO
3
.