Impact of TiO2 and NH3 on the Electronic Properties of Ge-Graphene Molecule for Gas Sensor Applications on Harmful Gases

A Density Functional Theory (DFT) has been carried out for the calculation of the molecular structure of the Ge-graphene molecule with Gaussian 09 and Gaussian view 5.08 programs. The effects of the doping TiO2 and NH3 grope atom have been performed by using DFT at B3LYP level with a 6-31G basis set. Based on first-principles calculations, it has been found out how sensitive a hybrid nitrogen-graphene nanosheet (N-doped graphene) is to the number of small gas molecules (CO, CO2, OH, and B2). The density of state, IR spectra, as well as the electrical and structural features, have all been studied. It is interesting to note that whereas CO adsorbed on N-doped graphene exhibits considerable chemisorption, other gases such as CO, CO2, OH, and B2 exhibit minor adsorption energies (Ead) between 0.75 and 1.15 eV. The smallest vacant molecular orbital (ELUMO), Fermi energy (Ef), and the highest molecular orbital that is occupied (EHOMO), as well as the energy band gap, all decrease as a result of the effects of CO and CO2 adsorption on electrical properties (Eg). The results of this paper point to the potential of a gas sensor for hazardous chemicals, this nanosheet (CO, CO2). This study explores the ammonia (NH3 and TiO2) adsorption impact on pure graphene layers by performing first-principles total energy DFT calculations.