Modelling for electric devices: Adsorption of polluted gases on g-ZnO monolayer

The gas sensing adsorption performance of the graphene-like two dimensional material, Zinc oxide monolayer (g-ZnO), was studied using first principle calculation to exploit its potential as polluted gas sensing materials. The common polluted gas molecules, CO, H₂S, NH₃, SO₂, NO and NO₂ were selected to examine their affinity with g-ZnO monolayer according to binding energy, charge transfer, adsorption distance and variation of the bond length and angle. The calculation results show that CO is weakly physically adsorbed on g-ZnO, while H₂S, NH₃ and NO exhibit relatively stronger interaction with g-ZnO with moderate adsorption energies in the range of - 0.375 to -0.618 eV. Likewise, SO₂ and NO₂ show the highest reactivity towards g-ZnO with the highest adsorption energies of -0.754 and -0.769 eV, respectively and the largest charge transfers and shortest adsorption distances. The results indicate that g-ZnO can be a suitable materials for the detection of H₂S, NH₃ and NO gases and also a promising candidates as a catalyst for SO₂ and NO₂.