Gas molecules (CO, NH$_3$, CO$_2$) sensing with Polyaniline Emardline salt (PANI ES) : a turbo TDDFT study

TL;DR

This study uses TD-DFT calculations to investigate how gas molecules like CO, NH$_3$, and CO$_2$ interact with Polyaniline Emeraldine salt, revealing optical response changes that could inform gas sensing applications.

Contribution

It provides a detailed computational analysis of gas adsorption effects on PANI ES's electronic and optical properties, highlighting NH$_3$ sensitivity.

Findings

NH$_3$ adsorption causes significant optical spectrum shifts.

Complex electronic features are more sensitive to NH$_3$.

Optical absorption spectra reveal shifts in λ_max depending on the complex.

Abstract

The adsorption of gas molecules (CO, NH$_3$, CO$_2$ ) on Polyaniline Emeraldine salt has been performed to study gas sensing. Density functional theory (DFT) and time dependent density functional theory (TD-DFT) calculations have been carried out to compute the response mechanism of polyaniline emeraldine salt (PANI ES) oligoanalinines (with two to six rings) to gas molecules. The optimized geometry and electronic structure corresponding to molecule and complexes are computed with the pseudo-potential and full-potential methods. The absorption spectra corresponding to polyaniline emeraldine salt molecule and its complexes are calculated using TD-DFT. We found it out that the electronic and optical features corresponding to complexes show more sensitive to the NH$_3$ adsorption. The optical absorption spectrum analysis was used for all ( nPANI ES-X ) and isolated nPANI ES. Then, the related spectrum indicates that the $\lambda_{max}$ is shifted red or blue, is affected by the kind of complex.