مشخصات پژوهش

First-principles calculations have been carried out to investigate the adsorption properties of SO2 molecules on N-doped TiO2 anatase nanoparticles using density functional theory (DFT) method in order to fully exploit the gas sensing capabilities of TiO2 particles. For this purpose, we have mainly studied the adsorption of SO2 molecule on the dangling oxygen atom and doped nitrogen atom sites of the TiO2 nanoparticles. Because these sites are more active than other sites in adsorption processes. The complex systems consisting of the SO2 molecule positioned toward the undoped and N-doped nanoparticles have been relaxed geometrically. The results presented are included structural parameters such as bond lengths and bond angles and energetics of the systems like adsorption energies. The electronic structure and the its variations resulted by the adsorption process, including the density of states (DOS), molecular orbitals and the charge transfer have been discussed. We found that the adsorption of SO2 molecule on the N-doped TiO2 nanoparticles is energetically more favorable than the adsorption on the undoped one. These results thus provide a theoretical basis for the potential applications of TiO2 nanoparticles in the removing and sensing of SO2 and give an explanation for helping in the optimization of improved gas removers and sensor devices.