Can magnetotransport properties provide insight into the functional groups in semiconducting MXenes?

Abstract

Hall scattering factors of Sc₂CF₂, Sc₂CO₂ and Sc₂C(OH)₂ are calculated using Rode's iterative approach by solving the Boltzmann transport equation. This is carried out in conjunction with calculations based on density functional theory. The electrical transport in Sc₂CF₂, Sc₂CO₂ and Sc₂C(OH)₂ is modelled by accounting for both elastic (acoustic and piezoelectric) and inelastic (polar optical phonon) scattering. Polar optical phonon (POP) scattering is the most significant mechanism in these MXenes. We observe that there is a window of carrier concentration where the Hall factor acts dramatically; Sc₂CF₂ obtains an incredibly high value of 2.49 while Sc₂CO₂ achieves a very small value of approximately 0.5, and Sc₂C(OH)₂ achieves the so called ideal value of 1. We propose in this paper that such Hall factor behaviour has significant promise in the field of surface group identification in MXenes, an issue that has long baffled researchers.