Magnetic single atom catalyst in C₂N to induce adsorption selectivity toward oxidizing gases

Density functional theory (DFT) method is used to study the effect of single-atom catalyst (SAC) of Mn embedded in C₂N nanoribbon (C₂N-NR) on the adsorption properties as an attempt to achieve selectivity. Many gases (e.g., CO, CO₂, H₂, H₂O, H₂S, N₂ and O₂) of interest to energy and environmental applications were tested. The results show that SAC-Mn alters chemisorption processes with all gas molecules except N₂. Clear adsorption selectivity is obtained towards oxidizing CO, CO₂ and O₂ molecules as evidenced by the enhancements in binding energy and charge transfer and the reduction in magnetization. While the SAC-Mn contributes predominantly to Fermi-energy region with spin-down states, the strong binding to oxidizing molecules introduces there more spin-up states to compromise and reduce the magnetization. Hence, C₂N-NR:Mn is proposed to be used as platform for gas sensor (if combined with magnetic sensor) to yield high selectivity toward these latter gases.