As a new and promising family of two-dimensional (2D) materials, MBenes have attracted attention owing to their excellent stability, high electrical conductivity, and versatile physicochemical properties. However, studies on the intrinsic physical properties of MBenes, including the superconductivity and band topology, are still relatively limited. In this study, we propose an effective strategy to regulate the superconducting and topological properties of ${\mathrm{Mo}}_2\mathrm{B}$ by combining surface functionalization and layer-number modulation based on first-principles calculations. Starting from pristine ${\mathrm{Mo}}_2\mathrm{B}$ in both the $1T$ and $2H$ phases, we investigate hydrogenated (${\mathrm{Mo}}_2{\mathrm{BH}}_2$), oxidized (${\mathrm{Mo}}_2{\mathrm{BO}}_2$), and quintuple-layer (${\mathrm{Mo}}_2{\mathrm{B}}_3$) derivatives. Thirteen thermodynamically and dynamically stable structures are identified. Among them, $H_1\text{−}{\mathrm{Mo}}_2{\mathrm{BO}}_2$ and $T_2\text{−}{\mathrm{Mo}}_2{\mathrm{B}}_3$ exhibit strong electron-phonon coupling and high superconducting transition temperatures of 32 and 28 K, respectively. Notably, $T_2\text{−}{\mathrm{Mo}}_2{\mathrm{B}}_3$ also shows nontrivial band topology characterized by a $Z_2$ index of 1 and topological edge states. Our findings uncover rich properties in ${\mathrm{Mo}}_2\mathrm{B}$-based MBenes and provide valuable insights for designing novel 2D materials with coexisting superconducting and topological states.

Close

PrevNext

View figure in article

• Superconductivity
• 2-dimensional systems
• Eliashberg theory
• First-principles calculations
• Wannier function methods