Adsorption effect of SO2 and CO2 gas molecules on ZnSe nanotube devices: first principles analysis

ZnSe nanotubes were constructed and optimized in order to analyze the adsorption behaviour of environmentally hazardous gases such as SO 2 and CO 2 by using density functional analysis. Different sites on the nanotubes, such as Zn and Se, were studied for adsorption energy, Mullikan population and the recovery time of the ZnSe nanotube during the adsorption process. The obtained results show that compared to SO 2 molecules, the ZnSe nanotubes are more reactive to CO 2 molecules. To study the electronic transport properties of the ZnSe nanotubes with and without gas molecules, a two-probe system was constructed and the transport properties were studied by implementing a non-equilibrium Green’s function. The transport properties were analyzed in terms of the device density of states, transmission curves and the V–I characteristics. The results confirm that the ZnSe nanotubes are more favourable for CO 2 molecules compared to the SO 2 molecules.