First-principles DFT study of SO₂ and SO₃ adsorption on 2PANI: a model for polyaniline response

ABSTRACT

Interaction of SO_x (x = 2,3) molecules on active sites of dianiline (as a model for polyaniline, denoted here as 2PANI) was studied using density functional theory at the BLYP-D/6-31+G(d) level of theory. Natural population analysis was used to find out the charge distribution as well as the net transferred charge of SO_x upon adsorption on 2PANI and the result has been compared with Mulliken charge analysis to evaluate the sensing ability of 2PANI. The computed density of states point to the remarkable orbital hybridization between SO_x and 2PANI during the adsorption process. As a consequence, the results of UV–VIS confirm the sensing ability of 2PANI toward SO₂ and SO₃. Based on our results, it can be found that at proper configuration the SO₂ and SO₃ molecules can be adsorbed on 2PANI with adsorption energies (E_ads) of −18.2 and −62.9 kJ/mol (BSSE), respectively.

GRAPHICAL ABSTRACT

KEYWORDS:

• DFT
• polyaniline
• SO₂
• SO₃
• HOMO–LUMO

ORCID

Ali Shokuhi Rad http://orcid.org/0000-0002-2426-0339