Surface Oxygen Passivation-Driven Large Anomalous Hall Conductivity in Early Transition Metal-Based Nitride MXenes: Can AHC Be a Tool to Determine Functional Groups in 2D Ferro(i)magnets?

Abstract

Identifying the existence of specific functional groups in MXenes is a difficult topic that has perplexed researchers for a long time. At the same time, the realization of intrinsic ferromagnetism, which is important for two-dimensional (2D) materials' families, is one of the fascinating properties that MXenes offer. Here, using first-principle calculations, we have examined the actual magneto-transport phenomena in transition metals and nitride-based-functionalized MXenes. We demonstrate that intrinsic anomalous Hall conductivity (AHC) can be used to identify the presence of more probable functional groups. The maximum AHC at Fermi energy, EF, is found in the case of Mn2NO2 (470 S/cm), which is attributed to the presence of avoided band crossing and a larger density of states. Together, when considering all the studied systems, the AHC can be above 2500 S/cm within EF +/- 0.25 eV. Our findings could be useful not only in guiding the experimentalists by considering AHC as a possible tool in determining the most probable functional groups in 2D ferro(i)magnets but also in designing memory devices with negligible stray fields.