Ab-Initio Characterization of Iron Embedded Nitrogen Doped Graphene as a Toxic Gas Sensor

Abstract Special binding sites in graphene are beneficial for near surface interaction. These binding sites are provided by single atom catalyst results in the modification of electronic characteristics of graphene and its derivatives which largely extend their application as gas sensors. In present work, transition metal atom iron supported on nitrogen doped graphene (FeN/G) was analyzed by density functional theory. The effect of gas adsorption on the structural and electronic properties were investigated with adsorption energy, charge transfer, work function and band structure. The results indicate chemisorption nature of CO, NO and NO2 with strong adsorption energies of -1.641 eV, -2.081 eV and − 1.345 eV. They induced spin polarization when adsorbed on the graphene support which drastically modulate the electronic characteristics of the substrate. While other gas molecules (CO2, H2S and NH3) with adsorption energies of -0.154 eV, -0.371 eV and − 0.46 eV were weakly physisorbed and electron donor in nature. SO2 exhibited weak chemisorption at a value of -0.62 eV. Nitrogen containing gas molecules of NO, NO2 and NH3 showed band gap shortening with increasing conductivity as compared to bare iron embedded graphene supported structure. On the basis of investigation, the structure has potential application for detection of NO and NO2.