Superconductivity of monolayer Mo₂C: The key role of functional groups

Monolayer Mo₂C is a new member of two-dimensional materials. Here the electronic structure and lattice dynamics of monolayer Mo₂C are calculated. According to the electron-phonon interaction, it is predicted that monolayer Mo₂C could be a quasi-two-dimensional superconductor and the effects of functional-groups are crucially important considering its unsaturated surface. Despite the suppressed superconductivity by chalcogen adsorption, our most interesting prediction is that the electron-phonon interaction of monolayer Mo₂C can be greatly enhanced by bromine absorption, suggesting that Mo₂CBr₂ as a good candidate for a nanoscale superconductor.