Adsorption of NH2NO2 molecule on the surface of pristine and Pt functionalized (6, 0) zigzag GaNNTs: A NMR study

In the recent years, the study of characteristics of nanotubes in gas phase and their use ingas sensors, storage of fuels, and removal of hazardous pollutants from gas streams is importantat many industrial processes [1–3]. So far, many different aspects of nanotube/adsorbents havebeen experimentally explored [4–5]. Moreover, different kinds of nanotubes such as (CNTs),(BNNTs), BeONTs, GaNNTs and SiCNTs have been theoretically investigated for gas moleculeadsorption. In this computational study, the representative models of NH2NO2 adsorption on thesurface of pristine and Pt functionalized (6, 0) zigzag GaNNTs are allowed to relax in theoptimization at the DFT level of B3LYP exchange functional and LAL2DZ standard basis set.From optimized structures the quantum and nuclear magnetic resonance parameters of systemare calculated. The chemical shielding tensors in principal axes system (PAS) are converted tomeasurable NMR parameters, chemical shielding isotropic (CSI) and chemical shieldinganisotropic (CSA) by Eqs 1 and 2.CSA(ppm)=σ(33) - (σ(11) + σ(22))/2 (1)CSI (ppm)= (σ(11) + σ(22) + σ(33))/3 (2)The calculated results demonstrate that with functionalizing Pt atoms on the surface of Gaand N atoms of nanotube the structural, electrical and optical parameters of nanotube altersignificantly from original state. On the other hand, with functionalizing Pt atoms the CSI valuesof Ga and N atoms increased significantly from original values, an so the electron chargesaround nanotube increased due to donor electron effect of Pt atoms. This result confirms that thesurface of nanotube is a good position to adsorb the nucleophile compound. The quantumparameters such global hardness and gap energy of system decrease. However, the NMRcalculated results demonstrate that the interaction between GaN nanotube and Nitroamide molecule inpresence of Pt atom is more favorable than other nanotube.

کلیدواژه ها:

GaNNTs ، DFT ، Pd Functionalized ، NMR