First principles insights into the electronic and magnetic properties of SnO2(110) doped with VIII-group transition metal single atom

Abstract

Inspired by the unprecedented surface chemical reaction activity of single-atom catalysts (SAC), this research presents a theoretical study on the doping of ${SnO}_2\left(110\right)$ surface with transition metal group VIII atoms (Fe, Co, Ni, Ru, Rh, Pd, Os, Ir, Pt). Using density functional theory (DFT), the formation energy, electronic structure, charge transfer and magnetic moments of the ${SnO}_2\left(110\right)$ system before and after doping were investigated. The formation energies of the different doped systems vary depending on the doping position. The doping of transition metal (TM) atoms can induce produces both charge transfer and magnetic moment. The charge transfer is largest in the Pd-doped system, with + 0.68 e at the position of the penta-coordinated Sn atom (${Sn}_{5c}$ position) and + 0.67 e at the position of the hexa-coordinated Sn atom (${Sn}_{6c}$ position), while the Co-doped system exhibits the smallest charge transfer of + 0.19 e (${Sn}_{6c}$ position). Fe, Co, Ni, Ru and Os atoms introduce magnetic moments, with the Fe-doped system (${Sn}_{5c}$ position) having the highest magnetic moments of 2.91 ${\mu }_B$. In the ${SnO}_2\left(110\right)$ surface system doped with TM atoms, there are varying degrees of orbital overlap between the TM atoms and their surrounding O atoms. This theoretical work provides valuable insights into the physical properties of metal oxide based single-atom catalysts.