Investigating the impact of mixed surface terminal groups and defect formation on the magnetic and electronic properties of Ti₂C MXene using the xTB Hamiltonian of the DFTB method

Two dimensional MXene materials have attracted considerable interest over the past few years due to their use in diverse applications, including biomedical [1], electronics [2], catalysis [3], and spintronics [4]. Moreover, it was found that the surface of the MXene material is usually functionalized by terminal groups, such as O [5], OH [6], F [6], Cl [6],... In addition, defect creation and mixed functionalization have been reported to modulate the electronic properties and the magnetic ordering in titanium based MXene [7,8], which can facilitate the use of these materials in diverse applications.

Here, we present a detailed study of the effect of defect creation and mixed surface termination on the electronic and magnetic properties of Ti₂C MXene. Calculations were performed using the density functional tight-binding (DFTB) method based on the extended tight binding (xTB) Hamiltonian [9].

References

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