Dynamical and turbo TDDFT study of polyaniline emeraldine for CO, NH3, CO2 gas sensing

• Published in: Applied physics. A, Materials science & processing Materials science & processing, 2020-06, Vol.126 (6), Article 428
• Main Authors: Hadian-Jazi, Nasim, Zare-Dehnavi, Nasser, Abdolhosseini-Sarsari, Ismaeil
• Format: Article
• Language: English
• Subjects: Absorption spectra; Adsorption; Ammonia; Applied physics; Carbon dioxide; Characterization and Evaluation of Materials; Condensed Matter Physics; Dipole moments; Electron states; Gas sensors; Hessian matrices; Machines; Manufacturing; Materials science; Molecular structure; Nanotechnology; Optical and Electronic Materials; Optimization; Perturbation; Physics; Physics and Astronomy; Polyanilines; Processes; Spectrum analysis; Surfaces and Interfaces; Thin Films; Time dependence
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-020-03506-5

The adsorption of gas molecules CO, NH 3 , CO 2 on polyaniline emeraldine salt affects its electronic states and IR active vibrational modes. Hartree–Fock/DFT hybrid functionals (HSE06) and Liouville–Lanczos approach, which implemented to solve time-dependent density-functional perturbation problem, have been carried out to compute the response mechanism (absorption spectra) of polyaniline emeraldine salt (PANI ES) oligoanalines (with two to six rings) to gas molecules after structure optimization. The optical absorption spectrum analysis of the all (nPANI ES-X) and isolated nPANI ES indicates that the λ max is shifted red or blue based on adsorbed gas type. We found it out that the electronic and optical features corresponding to complexes are more sensitive to the NH 3 adsorption. The vibrational modes and IR intensities were determined by Hessian matrix diagonalization and derivation of the dipole moments, respectively. The values of IR intensity and vibrational frequencies are changed by the number of PANI ES rings and also when gas molecules get absorbed on it.